<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <roleRef roleURI="http://www.paloaltonetworks.com/role/Acquisitions" xlink:href="panw-20150731.xsd#Acquisitions" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsAdditionalDetailsOfAcquisitionsDetails" xlink:href="panw-20150731.xsd#AcquisitionsAdditionalDetailsOfAcquisitionsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsConsiderationTransferredDetails" xlink:href="panw-20150731.xsd#AcquisitionsConsiderationTransferredDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsIntangibleAssetsAcquiredAsPartOfBusinessCombinationDetails" xlink:href="panw-20150731.xsd#AcquisitionsIntangibleAssetsAcquiredAsPartOfBusinessCombinationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsProFormaFinancialInformationDetails" xlink:href="panw-20150731.xsd#AcquisitionsProFormaFinancialInformationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsPurchasePriceAllocationCirrosecureDetails" xlink:href="panw-20150731.xsd#AcquisitionsPurchasePriceAllocationCirrosecureDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsPurchasePriceAllocationCyveraAndMortaDetails" xlink:href="panw-20150731.xsd#AcquisitionsPurchasePriceAllocationCyveraAndMortaDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/AcquisitionsTables" xlink:href="panw-20150731.xsd#AcquisitionsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingencies" xlink:href="panw-20150731.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesContractManufacturerCommitmentsDetails" xlink:href="panw-20150731.xsd#CommitmentsAndContingenciesContractManufacturerCommitmentsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesLeaseCommitmentScheduleDetails" xlink:href="panw-20150731.xsd#CommitmentsAndContingenciesLeaseCommitmentScheduleDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesLeasesDetails" xlink:href="panw-20150731.xsd#CommitmentsAndContingenciesLeasesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesRentExpenseDetails" xlink:href="panw-20150731.xsd#CommitmentsAndContingenciesRentExpenseDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesTables" xlink:href="panw-20150731.xsd#CommitmentsAndContingenciesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedBalanceSheets" xlink:href="panw-20150731.xsd#ConsolidatedBalanceSheets" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:href="panw-20150731.xsd#ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfCashFlows" xlink:href="panw-20150731.xsd#ConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfComprehensiveLoss" xlink:href="panw-20150731.xsd#ConsolidatedStatementsOfComprehensiveLoss" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfOperations" xlink:href="panw-20150731.xsd#ConsolidatedStatementsOfOperations" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:href="panw-20150731.xsd#ConsolidatedStatementsOfStockholdersEquity" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotes" xlink:href="panw-20150731.xsd#ConvertibleSeniorNotes" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesAdditionalInformationDetails" xlink:href="panw-20150731.xsd#ConvertibleSeniorNotesAdditionalInformationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesComponentsOfConvertibleSeniorNotesDetails" xlink:href="panw-20150731.xsd#ConvertibleSeniorNotesComponentsOfConvertibleSeniorNotesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesScheduleOfInterestExpenseRecognizedDetails" xlink:href="panw-20150731.xsd#ConvertibleSeniorNotesScheduleOfInterestExpenseRecognizedDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesTables" xlink:href="panw-20150731.xsd#ConvertibleSeniorNotesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPolicies" xlink:href="panw-20150731.xsd#DescriptionOfBusinessAndSummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAdvertisingCostsDetails" xlink:href="panw-20150731.xsd#DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAdvertisingCostsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConcentrationsDetails" xlink:href="panw-20150731.xsd#DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConcentrationsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConvertibleSeniorNotesDetails" xlink:href="panw-20150731.xsd#DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConvertibleSeniorNotesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:href="panw-20150731.xsd#DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/DocumentAndEntityInformationDocument" xlink:href="panw-20150731.xsd#DocumentAndEntityInformationDocument" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EmployeeBenefitPlan" xlink:href="panw-20150731.xsd#EmployeeBenefitPlan" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EmployeeBenefitPlanDetails" xlink:href="panw-20150731.xsd#EmployeeBenefitPlanDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EmployeeBenefitPlanTables" xlink:href="panw-20150731.xsd#EmployeeBenefitPlanTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlans" xlink:href="panw-20150731.xsd#EquityAwardPlans" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansAllocationOfShareBasedCompensationAdditionalInformationDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansAllocationOfShareBasedCompensationAdditionalInformationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansAllocationOfShareBasedCompensationExpenseByFunctionalAreaDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansAllocationOfShareBasedCompensationExpenseByFunctionalAreaDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansEmployeeStockPurchasePlanValuationAssumptionsDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansEmployeeStockPurchasePlanValuationAssumptionsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansRsusActivitiesDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansRsusActivitiesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansShareBasedCompensationPlansDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansShareBasedCompensationPlansDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansSharesAvailableForGrantRollForwardDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansSharesAvailableForGrantRollForwardDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansStockOptionsActivityDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansStockOptionsActivityDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansStockOptionsValuationAssumptionsDetails" xlink:href="panw-20150731.xsd#EquityAwardPlansStockOptionsValuationAssumptionsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/EquityAwardPlansTables" xlink:href="panw-20150731.xsd#EquityAwardPlansTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/FairValueMeasurements" xlink:href="panw-20150731.xsd#FairValueMeasurements" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/FairValueMeasurementsDetails" xlink:href="panw-20150731.xsd#FairValueMeasurementsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/FairValueMeasurementsTables" xlink:href="panw-20150731.xsd#FairValueMeasurementsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssets" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssets" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsAmortizationExpenseDetails" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssetsAmortizationExpenseDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsFutureAmortizationExpenseDetails" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssetsFutureAmortizationExpenseDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsGoodwillRollForwardDetails" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssetsGoodwillRollForwardDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsIntangibleAssetsAndRelatedAmortizationDetails" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssetsIntangibleAssetsAndRelatedAmortizationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsTables" xlink:href="panw-20150731.xsd#GoodwillAndIntangibleAssetsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxes" xlink:href="panw-20150731.xsd#IncomeTaxes" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesAdditionalInformationDetails" xlink:href="panw-20150731.xsd#IncomeTaxesAdditionalInformationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesComponentsOfDeferredTaxAssetsAndLiabilitiesDetails" xlink:href="panw-20150731.xsd#IncomeTaxesComponentsOfDeferredTaxAssetsAndLiabilitiesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesEffectiveTaxReconciliationDetails" xlink:href="panw-20150731.xsd#IncomeTaxesEffectiveTaxReconciliationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesLossBeforeProvisionForIncomeTaxesDetails" xlink:href="panw-20150731.xsd#IncomeTaxesLossBeforeProvisionForIncomeTaxesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesNetOperatingLossCarryforwardDetails" xlink:href="panw-20150731.xsd#IncomeTaxesNetOperatingLossCarryforwardDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxExpenseDetails" xlink:href="panw-20150731.xsd#IncomeTaxesScheduleOfComponentsOfIncomeTaxExpenseDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesTables" xlink:href="panw-20150731.xsd#IncomeTaxesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesTaxCreditCarryforwardsDetails" xlink:href="panw-20150731.xsd#IncomeTaxesTaxCreditCarryforwardsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesUnrecognizedTaxBenefitRollForwarddetails" xlink:href="panw-20150731.xsd#IncomeTaxesUnrecognizedTaxBenefitRollForwarddetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/IncomeTaxesValuationAllowanceDetails" xlink:href="panw-20150731.xsd#IncomeTaxesValuationAllowanceDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/Investments" xlink:href="panw-20150731.xsd#Investments" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsContractualMaturitiesDetails" xlink:href="panw-20150731.xsd#InvestmentsAvailableForSaleInvestmentsContractualMaturitiesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsDetails" xlink:href="panw-20150731.xsd#InvestmentsAvailableForSaleInvestmentsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsInUnrealizedLossPositionDetails" xlink:href="panw-20150731.xsd#InvestmentsAvailableForSaleInvestmentsInUnrealizedLossPositionDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/InvestmentsProceedsFromSalesOfInvestmentsDetails" xlink:href="panw-20150731.xsd#InvestmentsProceedsFromSalesOfInvestmentsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/InvestmentsTables" xlink:href="panw-20150731.xsd#InvestmentsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/LegalSettlement" xlink:href="panw-20150731.xsd#LegalSettlement" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/LegalSettlementDetails" xlink:href="panw-20150731.xsd#LegalSettlementDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/LegalSettlementTables" xlink:href="panw-20150731.xsd#LegalSettlementTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/NetIncomeLossPerShare" xlink:href="panw-20150731.xsd#NetIncomeLossPerShare" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareComputationOfBasicAndDilutedNetIncomeLossPerShareDetails" xlink:href="panw-20150731.xsd#NetIncomeLossPerShareComputationOfBasicAndDilutedNetIncomeLossPerShareDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareScheduleOfAntidilutiveSecuritiesExcludedFromComputationDetails" xlink:href="panw-20150731.xsd#NetIncomeLossPerShareScheduleOfAntidilutiveSecuritiesExcludedFromComputationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareTables" xlink:href="panw-20150731.xsd#NetIncomeLossPerShareTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/PropertyAndEquipment" xlink:href="panw-20150731.xsd#PropertyAndEquipment" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/PropertyAndEquipmentDepreciationExpenseDetails" xlink:href="panw-20150731.xsd#PropertyAndEquipmentDepreciationExpenseDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/PropertyAndEquipmentPropertyAndEquipmentByTypeDetails" xlink:href="panw-20150731.xsd#PropertyAndEquipmentPropertyAndEquipmentByTypeDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/PropertyAndEquipmentTables" xlink:href="panw-20150731.xsd#PropertyAndEquipmentTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SegmentInformation" xlink:href="panw-20150731.xsd#SegmentInformation" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SegmentInformationRevenueByGeographicTheaterDetails" xlink:href="panw-20150731.xsd#SegmentInformationRevenueByGeographicTheaterDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SegmentInformationRevenueFromExternalCustomersByProductsAndServicesDetails" xlink:href="panw-20150731.xsd#SegmentInformationRevenueFromExternalCustomersByProductsAndServicesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SegmentInformationTables" xlink:href="panw-20150731.xsd#SegmentInformationTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnaudited" xlink:href="panw-20150731.xsd#SelectedQuarterlyFinancialDataUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnauditedDetails" xlink:href="panw-20150731.xsd#SelectedQuarterlyFinancialDataUnauditedDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnauditedTables" xlink:href="panw-20150731.xsd#SelectedQuarterlyFinancialDataUnauditedTables" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/StockholdersEquity" xlink:href="panw-20150731.xsd#StockholdersEquity" xlink:type="simple" />
  <roleRef roleURI="http://www.paloaltonetworks.com/role/StockholdersEquitySecondaryOfferingDetails" xlink:href="panw-20150731.xsd#StockholdersEquitySecondaryOfferingDetails" xlink:type="simple" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/Acquisitions" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsAdditionalDetailsOfAcquisitionsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsConsiderationTransferredDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsIntangibleAssetsAcquiredAsPartOfBusinessCombinationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsProFormaFinancialInformationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsPurchasePriceAllocationCirrosecureDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsPurchasePriceAllocationCyveraAndMortaDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_5768b9cc-0ed4-c9f7-ae9d-514cfaf00027" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_5768b9cc-0ed4-c9f7-ae9d-514cfaf00027" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_b108d604-1348-4e65-3817-2944b734c65a" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_Goodwill_b108d604-1348-4e65-3817-2944b734c65a" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_bcb36c16-bb23-6f85-9116-c0904e7dcadf" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_bcb36c16-bb23-6f85-9116-c0904e7dcadf" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_8e82af62-5d0c-8a44-003d-d4557b49ee76" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_8e82af62-5d0c-8a44-003d-d4557b49ee76" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent_b0419091-032e-c384-ce03-ca388d51379a" xlink:type="locator" />
    <calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent_b0419091-032e-c384-ce03-ca388d51379a" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_38b908d0-3ddf-2ab7-5076-d76b2cb8c9a7" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_603f073e-ba37-8b22-802f-84d073637bea" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_38b908d0-3ddf-2ab7-5076-d76b2cb8c9a7" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/AcquisitionsTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingencies" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesContractManufacturerCommitmentsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesLeaseCommitmentScheduleDetails" xlink:type="extended">
    <loc xlink:href="panw-20150731.xsd#panw_OperatingLeasesFutureMinimumPaymentsDueExcludingSubleaseIncome" xlink:label="loc_panw_OperatingLeasesFutureMinimumPaymentsDueExcludingSubleaseIncome_ef3223a7-8e16-2774-7072-9012c66ff045" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_panw_OperatingLeasesFutureMinimumPaymentsDueExcludingSubleaseIncome_ef3223a7-8e16-2774-7072-9012c66ff045" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_8a0692b4-cb50-1eeb-12b4-1509099841b7" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_8a0692b4-cb50-1eeb-12b4-1509099841b7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_4c8190eb-f692-81f2-35bc-182f11d12444" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_4c8190eb-f692-81f2-35bc-182f11d12444" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_baee32aa-bbe2-ead3-1f78-a80f542a97a2" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_baee32aa-bbe2-ead3-1f78-a80f542a97a2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_5e342c11-473b-4170-d672-935adcfdb463" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_5e342c11-473b-4170-d672-935adcfdb463" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_c48f63ae-e409-59ce-5794-cc7ae6139c21" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_c48f63ae-e409-59ce-5794-cc7ae6139c21" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6adcb5b9-fb65-97ee-8a5b-2e780c178728" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6282e4c0-b0bd-9c84-bf43-857ac02b98fc" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6adcb5b9-fb65-97ee-8a5b-2e780c178728" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals_b0846bba-bbff-1184-b279-4fd3a9548e33" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_panw_OperatingLeasesFutureMinimumPaymentsDueExcludingSubleaseIncome_ef3223a7-8e16-2774-7072-9012c66ff045" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals_b0846bba-bbff-1184-b279-4fd3a9548e33" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesLeasesDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesRentExpenseDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/CommitmentsAndContingenciesTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedBalanceSheets" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_22caddf9-3843-6329-6e39-dc458323b572" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:to="loc_us-gaap_AccountsPayableCurrent_22caddf9-3843-6329-6e39-dc458323b572" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_edc340b7-5c57-03d7-7d1e-ad6feb822363" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_edc340b7-5c57-03d7-7d1e-ad6feb822363" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_b0e22c2c-56ff-3d71-c26d-db5b29d489ae" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:to="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_b0e22c2c-56ff-3d71-c26d-db5b29d489ae" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_a33614ee-2047-2d07-d4dc-cd97b29aa0eb" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:to="loc_us-gaap_DeferredRevenueCurrent_a33614ee-2047-2d07-d4dc-cd97b29aa0eb" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ConvertibleDebtCurrent" xlink:label="loc_us-gaap_ConvertibleDebtCurrent_2d5eb79b-f357-44de-9fc5-df0f0445e918" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_1de50dbc-01a9-6657-f83f-d1e74edfdf18" xlink:to="loc_us-gaap_ConvertibleDebtCurrent_2d5eb79b-f357-44de-9fc5-df0f0445e918" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ConvertibleDebtNoncurrent" xlink:label="loc_us-gaap_ConvertibleDebtNoncurrent_44bfe34f-986b-7cbf-4266-e80d9b9323db" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_ConvertibleDebtNoncurrent_44bfe34f-986b-7cbf-4266-e80d9b9323db" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredRevenueNoncurrent" xlink:label="loc_us-gaap_DeferredRevenueNoncurrent_4ca8aac1-2306-11d6-0ee3-d0bcb454b02f" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_DeferredRevenueNoncurrent_4ca8aac1-2306-11d6-0ee3-d0bcb454b02f" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_7f5c7cfd-4659-429c-35ab-266d67961421" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_7f5c7cfd-4659-429c-35ab-266d67961421" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue_359b0ac4-80ce-a291-f73b-cff103b81eae" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:to="loc_us-gaap_PreferredStockValue_359b0ac4-80ce-a291-f73b-cff103b81eae" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_ce40a301-9b6b-9fc3-bfb6-dfbb8fcdf29b" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:to="loc_us-gaap_CommonStockValue_ce40a301-9b6b-9fc3-bfb6-dfbb8fcdf29b" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdditionalPaidInCapitalCommonStock" xlink:label="loc_us-gaap_AdditionalPaidInCapitalCommonStock_8d1ec446-d346-e57d-d34b-0cb90bceaaba" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:to="loc_us-gaap_AdditionalPaidInCapitalCommonStock_8d1ec446-d346-e57d-d34b-0cb90bceaaba" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_1d565cd0-d7bf-de89-4dbe-a484007b1fe8" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_1d565cd0-d7bf-de89-4dbe-a484007b1fe8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_dd6b7206-c19f-4dd5-339b-1369c57cfe0f" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_d0f349aa-18e3-6323-86ad-665f8773c064" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_dd6b7206-c19f-4dd5-339b-1369c57cfe0f" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:label="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent_79c147c7-75fa-5f99-b783-fd4d059d0894" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_4a314f0d-c6fa-5cf2-0be1-add747465af3" xlink:to="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent_79c147c7-75fa-5f99-b783-fd4d059d0894" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_cd34decb-53b6-e0a9-28d5-0a9741c4b0f8" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_cd34decb-53b6-e0a9-28d5-0a9741c4b0f8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_4d24e56f-a5cb-07ba-0508-f5f1533ae24e" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_4d24e56f-a5cb-07ba-0508-f5f1533ae24e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_f186537c-a0b4-9ca7-f59a-958a18f111e6" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_f186537c-a0b4-9ca7-f59a-958a18f111e6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesCurrent" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesCurrent_222b5a74-9526-7448-da46-fccf1775d7c0" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_39eaeb62-7ee3-5503-48f5-08c2dff05e50" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesCurrent_222b5a74-9526-7448-da46-fccf1775d7c0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_7ce178a4-245f-fa78-36a1-552609a67554" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_7ce178a4-245f-fa78-36a1-552609a67554" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesNoncurrent" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesNoncurrent_392a46ef-05fd-68f8-e487-35e85a8f15a1" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesNoncurrent_392a46ef-05fd-68f8-e487-35e85a8f15a1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_b108d604-1348-4e65-3817-2944b734c65a" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_Goodwill_b108d604-1348-4e65-3817-2944b734c65a" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_894a128f-2068-d267-1e3e-64c93d0ed5ca" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_894a128f-2068-d267-1e3e-64c93d0ed5ca" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_9b98e689-e6db-3e5b-e5c3-3324fffb4edf" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_effc14df-fd72-eec8-ede9-64e0071b91bc" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_9b98e689-e6db-3e5b-e5c3-3324fffb4edf" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfCashFlows" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_ff5db18e-7b91-5a5d-e914-0527b02a8012" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_ff5db18e-7b91-5a5d-e914-0527b02a8012" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecurities_11bab1ef-563b-9c08-d855-5223ff2c6591" xlink:type="locator" />
    <calculationArc order="1" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecurities_11bab1ef-563b-9c08-d855-5223ff2c6591" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities_bb2533a8-a0f5-8219-15a5-93b1de4f7dc3" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities_bb2533a8-a0f5-8219-15a5-93b1de4f7dc3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:label="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_40a15540-5505-f065-d19f-d46c007caf39" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:to="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_40a15540-5505-f065-d19f-d46c007caf39" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_4852d3ee-c33e-1b07-798c-41e651367343" xlink:type="locator" />
    <calculationArc order="4" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_4852d3ee-c33e-1b07-798c-41e651367343" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireProductiveAssets" xlink:label="loc_us-gaap_PaymentsToAcquireProductiveAssets_e99298f8-8539-2c5d-71eb-dc2c98dbf148" xlink:type="locator" />
    <calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_58a5bd26-e5f4-de8f-6118-f713733148b8" xlink:to="loc_us-gaap_PaymentsToAcquireProductiveAssets_e99298f8-8539-2c5d-71eb-dc2c98dbf148" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_ff5db18e-7b91-5a5d-e914-0527b02a8012" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_d4c99b59-c44a-c4ac-309f-0bddfdb944a5" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_ShareBasedCompensation_d4c99b59-c44a-c4ac-309f-0bddfdb944a5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherNoncashExpense" xlink:label="loc_us-gaap_OtherNoncashExpense_116f65e2-2406-9b7b-d73e-3e2903462735" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_OtherNoncashExpense_116f65e2-2406-9b7b-d73e-3e2903462735" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_783b94c5-664a-4bc7-f813-8c258cc934b7" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_783b94c5-664a-4bc7-f813-8c258cc934b7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments" xlink:label="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_3ef3660d-f952-6ded-6018-37f75b491ea0" xlink:type="locator" />
    <calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_3ef3660d-f952-6ded-6018-37f75b491ea0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_8cbefbd3-c0da-e8cd-4d05-220ea9ed4d75" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_8cbefbd3-c0da-e8cd-4d05-220ea9ed4d75" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:label="loc_us-gaap_FairValueAdjustmentOfWarrants_62790e96-2cfd-e84e-131c-ca4fa0c495e1" xlink:type="locator" />
    <calculationArc order="7" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_FairValueAdjustmentOfWarrants_62790e96-2cfd-e84e-131c-ca4fa0c495e1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities" xlink:label="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_b841fb4f-3c0e-cd5c-bbc1-86e011a106f2" xlink:type="locator" />
    <calculationArc order="8" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_b841fb4f-3c0e-cd5c-bbc1-86e011a106f2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherNoncashIncomeExpense" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_8a9fbf97-3c14-4351-6d6b-553e136a9df1" xlink:type="locator" />
    <calculationArc order="9" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_OtherNoncashIncomeExpense_8a9fbf97-3c14-4351-6d6b-553e136a9df1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_91d80b53-6368-7466-a11d-02030d33de5c" xlink:type="locator" />
    <calculationArc order="10" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_91d80b53-6368-7466-a11d-02030d33de5c" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_709900d0-f7b0-b950-eae5-eeb8fc36b367" xlink:type="locator" />
    <calculationArc order="11" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_709900d0-f7b0-b950-eae5-eeb8fc36b367" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_a167e25c-e8b1-aeb8-f355-3727e3f06f3e" xlink:type="locator" />
    <calculationArc order="12" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_a167e25c-e8b1-aeb8-f355-3727e3f06f3e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_2b4cdf2a-798e-d1cb-6ae3-f35d605be735" xlink:type="locator" />
    <calculationArc order="13" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_2b4cdf2a-798e-d1cb-6ae3-f35d605be735" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_1d5377b2-ec05-33fd-26fe-62d3fd26bc4d" xlink:type="locator" />
    <calculationArc order="14" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_1d5377b2-ec05-33fd-26fe-62d3fd26bc4d" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredRevenue" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_ccf69244-7aaf-19cf-90d6-269f163732c4" xlink:type="locator" />
    <calculationArc order="15" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_916e1eb7-21fa-e5f0-a15f-0b05ed633776" xlink:to="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_ccf69244-7aaf-19cf-90d6-269f163732c4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_ff5db18e-7b91-5a5d-e914-0527b02a8012" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromConvertibleDebt" xlink:label="loc_us-gaap_ProceedsFromConvertibleDebt_a6f328a5-e0b8-0231-dfe0-76c91d5804e5" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_ProceedsFromConvertibleDebt_a6f328a5-e0b8-0231-dfe0-76c91d5804e5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfWarrants_b60e260e-6aaf-6c57-889e-f58f371ba2b6" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfWarrants_b60e260e-6aaf-6c57-889e-f58f371ba2b6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsForHedgeFinancingActivities" xlink:label="loc_us-gaap_PaymentsForHedgeFinancingActivities_09a61271-c443-465b-905e-1b33d6f42dde" xlink:type="locator" />
    <calculationArc order="3" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_PaymentsForHedgeFinancingActivities_09a61271-c443-465b-905e-1b33d6f42dde" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions_fdef3cb2-ec10-67c4-c0cc-b6e268faa4f7" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions_fdef3cb2-ec10-67c4-c0cc-b6e268faa4f7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities" xlink:label="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_9dbeb004-67a9-1b19-c357-8b5cbf0013ee" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_9dbeb004-67a9-1b19-c357-8b5cbf0013ee" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_3ae827d8-ec87-3579-cdaf-badc9bda2267" xlink:type="locator" />
    <calculationArc order="6" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_3ae827d8-ec87-3579-cdaf-badc9bda2267" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_4c2e87e5-41d0-b35b-6dfd-e3ab5b253709" xlink:type="locator" />
    <calculationArc order="7" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a678c20d-a481-ef6a-800a-4bd566075d81" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_4c2e87e5-41d0-b35b-6dfd-e3ab5b253709" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfComprehensiveLoss" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_640557c9-9806-6bef-9084-9cc792948f77" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_640557c9-9806-6bef-9084-9cc792948f77" xlink:to="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8449f638-e094-e8fc-6726-9e09a5f21c54" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_640557c9-9806-6bef-9084-9cc792948f77" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8449f638-e094-e8fc-6726-9e09a5f21c54" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_7a0c4985-9166-79eb-6063-d5e6ffb820df" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8449f638-e094-e8fc-6726-9e09a5f21c54" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_7a0c4985-9166-79eb-6063-d5e6ffb820df" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_1c4a86dc-184f-b6a9-3882-e4b9077e09ca" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8449f638-e094-e8fc-6726-9e09a5f21c54" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_1c4a86dc-184f-b6a9-3882-e4b9077e09ca" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfOperations" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_0ea1551e-1643-5e21-4c6e-6431fd87aa68" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:to="loc_us-gaap_OperatingIncomeLoss_0ea1551e-1643-5e21-4c6e-6431fd87aa68" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_ae720951-4a78-255d-8bd1-88ff26a27caf" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_0ea1551e-1643-5e21-4c6e-6431fd87aa68" xlink:to="loc_us-gaap_GrossProfit_ae720951-4a78-255d-8bd1-88ff26a27caf" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SalesRevenueNet" xlink:label="loc_us-gaap_SalesRevenueNet_533a4e74-899a-26d7-f9ea-a738a9e615c4" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_ae720951-4a78-255d-8bd1-88ff26a27caf" xlink:to="loc_us-gaap_SalesRevenueNet_533a4e74-899a-26d7-f9ea-a738a9e615c4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SalesRevenueGoodsNet" xlink:label="loc_us-gaap_SalesRevenueGoodsNet_ca646ab3-5159-77d2-80af-f70eebc0f27d" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_SalesRevenueNet_533a4e74-899a-26d7-f9ea-a738a9e615c4" xlink:to="loc_us-gaap_SalesRevenueGoodsNet_ca646ab3-5159-77d2-80af-f70eebc0f27d" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SalesRevenueServicesNet" xlink:label="loc_us-gaap_SalesRevenueServicesNet_44dc9933-9f90-1918-a915-8c3bdaeb5909" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_SalesRevenueNet_533a4e74-899a-26d7-f9ea-a738a9e615c4" xlink:to="loc_us-gaap_SalesRevenueServicesNet_44dc9933-9f90-1918-a915-8c3bdaeb5909" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_a64684b5-99de-91bb-54dd-5702d4624c68" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_ae720951-4a78-255d-8bd1-88ff26a27caf" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_a64684b5-99de-91bb-54dd-5702d4624c68" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CostOfGoodsSold" xlink:label="loc_us-gaap_CostOfGoodsSold_47bf16bc-113d-838a-56d3-e154f0f2a154" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CostOfGoodsAndServicesSold_a64684b5-99de-91bb-54dd-5702d4624c68" xlink:to="loc_us-gaap_CostOfGoodsSold_47bf16bc-113d-838a-56d3-e154f0f2a154" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CostOfServices" xlink:label="loc_us-gaap_CostOfServices_6058f4b1-4b85-3102-852a-5038aa25f911" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CostOfGoodsAndServicesSold_a64684b5-99de-91bb-54dd-5702d4624c68" xlink:to="loc_us-gaap_CostOfServices_6058f4b1-4b85-3102-852a-5038aa25f911" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_0ea1551e-1643-5e21-4c6e-6431fd87aa68" xlink:to="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_6a3cb05a-f9c0-32f6-d20f-a948f53d0ee5" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_6a3cb05a-f9c0-32f6-d20f-a948f53d0ee5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaap_SellingAndMarketingExpense_4466c9c2-563e-0e4c-244e-504a0a74eee1" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:to="loc_us-gaap_SellingAndMarketingExpense_4466c9c2-563e-0e4c-244e-504a0a74eee1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_69f193f1-2583-2a25-604c-cc949229c2d8" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_69f193f1-2583-2a25-604c-cc949229c2d8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GainLossRelatedToLitigationSettlement" xlink:label="loc_us-gaap_GainLossRelatedToLitigationSettlement_949f3a42-554b-2724-dfc3-2d682510f18b" xlink:type="locator" />
    <calculationArc order="4" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_8d80f9f2-ec8e-5a02-2390-b5ea959a18b0" xlink:to="loc_us-gaap_GainLossRelatedToLitigationSettlement_949f3a42-554b-2724-dfc3-2d682510f18b" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_8d3aa4ad-dbea-9eba-4578-5d3b83ba3bc6" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:to="loc_us-gaap_InterestExpense_8d3aa4ad-dbea-9eba-4578-5d3b83ba3bc6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_915682f7-b9cc-2ed3-6852-178ddfcb101f" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_915682f7-b9cc-2ed3-6852-178ddfcb101f" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_e62ce8b8-4401-2622-8598-3e644745e95e" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotes" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesAdditionalInformationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesComponentsOfConvertibleSeniorNotesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_9210187e-cdda-2312-446f-000237db141c" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_b2da023b-baa1-abbb-dd80-71732fab3756" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_9210187e-cdda-2312-446f-000237db141c" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_b2da023b-baa1-abbb-dd80-71732fab3756" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_c3000348-a725-d2d5-9bf2-c508e22f5f25" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_9210187e-cdda-2312-446f-000237db141c" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_c3000348-a725-d2d5-9bf2-c508e22f5f25" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesScheduleOfInterestExpenseRecognizedDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_303ddad1-c92e-dee8-e988-6fa7a693d02e" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_9b0336f3-1570-e518-771d-91dfd9dbbc96" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_303ddad1-c92e-dee8-e988-6fa7a693d02e" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_9b0336f3-1570-e518-771d-91dfd9dbbc96" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="loc_us-gaap_AmortizationOfDebtDiscountPremium_dfec2b16-4a43-7264-ec3d-010772e15534" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_303ddad1-c92e-dee8-e988-6fa7a693d02e" xlink:to="loc_us-gaap_AmortizationOfDebtDiscountPremium_dfec2b16-4a43-7264-ec3d-010772e15534" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/ConvertibleSeniorNotesTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPolicies" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAdvertisingCostsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConcentrationsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesConvertibleSeniorNotesDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/DocumentAndEntityInformationDocument" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EmployeeBenefitPlan" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EmployeeBenefitPlanDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EmployeeBenefitPlanTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlans" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansAllocationOfShareBasedCompensationAdditionalInformationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansAllocationOfShareBasedCompensationExpenseByFunctionalAreaDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansEmployeeStockPurchasePlanValuationAssumptionsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansRsusActivitiesDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansShareBasedCompensationPlansDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansSharesAvailableForGrantRollForwardDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansStockOptionsActivityDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansStockOptionsValuationAssumptionsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/EquityAwardPlansTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/FairValueMeasurements" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/FairValueMeasurementsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/FairValueMeasurementsTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssets" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsAmortizationExpenseDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsFutureAmortizationExpenseDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsGoodwillRollForwardDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsIntangibleAssetsAndRelatedAmortizationDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_894a128f-2068-d267-1e3e-64c93d0ed5ca" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_ba3ee58c-a1d2-0b1b-d8ba-aeea5e112c4e" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_894a128f-2068-d267-1e3e-64c93d0ed5ca" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_ba3ee58c-a1d2-0b1b-d8ba-aeea5e112c4e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_0b66a991-68b5-43d2-3cb3-4ea68bba2b7e" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_ba3ee58c-a1d2-0b1b-d8ba-aeea5e112c4e" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_0b66a991-68b5-43d2-3cb3-4ea68bba2b7e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_37242da4-8bd9-8845-4f04-4d33ee3aa769" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_ba3ee58c-a1d2-0b1b-d8ba-aeea5e112c4e" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_37242da4-8bd9-8845-4f04-4d33ee3aa769" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_5fad788a-33b8-6ace-c3c4-7d91cd9f63e4" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_894a128f-2068-d267-1e3e-64c93d0ed5ca" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_5fad788a-33b8-6ace-c3c4-7d91cd9f63e4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_d1f67248-e9b5-f4cc-7b0f-6057f1a3d17a" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_d1f67248-e9b5-f4cc-7b0f-6057f1a3d17a" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_0b66a991-68b5-43d2-3cb3-4ea68bba2b7e" xlink:type="arc" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_d1f67248-e9b5-f4cc-7b0f-6057f1a3d17a" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_5fad788a-33b8-6ace-c3c4-7d91cd9f63e4" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/GoodwillAndIntangibleAssetsTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxes" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesAdditionalInformationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesComponentsOfDeferredTaxAssetsAndLiabilitiesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_7ab95885-50a1-f3b5-4737-49b616fc51d6" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilities" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities_3e14f64d-d2f6-3fdd-a49d-772a2e1ab66a" xlink:type="locator" />
    <calculationArc order="1" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_7ab95885-50a1-f3b5-4737-49b616fc51d6" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilities_3e14f64d-d2f6-3fdd-a49d-772a2e1ab66a" xlink:type="arc" />
    <loc xlink:href="panw-20150731.xsd#panw_Deferredtaxliabilitiesfixedassetsandintangibleassets" xlink:label="loc_panw_Deferredtaxliabilitiesfixedassetsandintangibleassets_47f7a12b-84a9-9d7a-2de8-bea7eebc3c64" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_3e14f64d-d2f6-3fdd-a49d-772a2e1ab66a" xlink:to="loc_panw_Deferredtaxliabilitiesfixedassetsandintangibleassets_47f7a12b-84a9-9d7a-2de8-bea7eebc3c64" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxLiabilitiesOther" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther_24ce0b8b-7683-acd6-b39f-77940dbca72b" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_3e14f64d-d2f6-3fdd-a49d-772a2e1ab66a" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesOther_24ce0b8b-7683-acd6-b39f-77940dbca72b" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsNet" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_c9103802-e01c-0411-2da8-2206c8e6cbaf" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_7ab95885-50a1-f3b5-4737-49b616fc51d6" xlink:to="loc_us-gaap_DeferredTaxAssetsNet_c9103802-e01c-0411-2da8-2206c8e6cbaf" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsGross" xlink:label="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_c9103802-e01c-0411-2da8-2206c8e6cbaf" xlink:to="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals_4c951502-27e1-4d57-0b38-4c553c9cf62f" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals_4c951502-27e1-4d57-0b38-4c553c9cf62f" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsDeferredIncome" xlink:label="loc_us-gaap_DeferredTaxAssetsDeferredIncome_2bda83ba-0db3-98b0-761b-d8fe7c271584" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:to="loc_us-gaap_DeferredTaxAssetsDeferredIncome_2bda83ba-0db3-98b0-761b-d8fe7c271584" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_351e9f9c-f3e3-2db3-110c-394de97ab52e" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_351e9f9c-f3e3-2db3-110c-394de97ab52e" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_2388bf7d-bac3-63e4-7ea0-6e9febb628dd" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:to="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_2388bf7d-bac3-63e4-7ea0-6e9febb628dd" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_11af201b-713a-e639-e3e5-2a2e9be5b0c6" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_ae76b0a4-0e26-3d8f-4ecb-c8186dd802d0" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_11af201b-713a-e639-e3e5-2a2e9be5b0c6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_43429341-a7f8-3d28-8300-64e1feef8fa0" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_c9103802-e01c-0411-2da8-2206c8e6cbaf" xlink:to="loc_us-gaap_DeferredTaxAssetsValuationAllowance_43429341-a7f8-3d28-8300-64e1feef8fa0" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesEffectiveTaxReconciliationDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_acf5d13d-61d7-58c0-7f7b-a5c0f7cb7066" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_acf5d13d-61d7-58c0-7f7b-a5c0f7cb7066" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_4b3be44f-5687-e783-ac34-c53c5c3f10e0" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_4b3be44f-5687-e783-ac34-c53c5c3f10e0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_79b52493-ed4b-fb62-5daf-e1982275e67b" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_79b52493-ed4b-fb62-5daf-e1982275e67b" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_ae3561e4-ce43-53a8-871d-507f741a2369" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_ae3561e4-ce43-53a8-871d-507f741a2369" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_89addf3c-f7bf-964a-aba6-4e5ca9958acd" xlink:type="locator" />
    <calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_89addf3c-f7bf-964a-aba6-4e5ca9958acd" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment_55d7599a-f1bc-ed24-549e-95e511296704" xlink:type="locator" />
    <calculationArc order="6" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment_55d7599a-f1bc-ed24-549e-95e511296704" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAmortization" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAmortization_0f060cd2-9967-b51c-4e43-22fc6dab1f2f" xlink:type="locator" />
    <calculationArc order="7" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAmortization_0f060cd2-9967-b51c-4e43-22fc6dab1f2f" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_6bbeca8f-a74f-62c9-14cf-944a068a4d23" xlink:type="locator" />
    <calculationArc order="8" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_6bbeca8f-a74f-62c9-14cf-944a068a4d23" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_750737d4-a9f6-ddcb-7238-bbe8eadd7390" xlink:type="locator" />
    <calculationArc order="9" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_037594ef-c95d-7169-0f2c-0d9bf9c6587e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_750737d4-a9f6-ddcb-7238-bbe8eadd7390" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesLossBeforeProvisionForIncomeTaxesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_e8c93fd8-b953-0fac-1368-bda1875af048" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_e8c93fd8-b953-0fac-1368-bda1875af048" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_6a037740-99db-8b3b-3911-f1b1e7885e0c" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_f0ea1b66-a9f7-f42c-6882-4cca5faefea1" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_6a037740-99db-8b3b-3911-f1b1e7885e0c" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesNetOperatingLossCarryforwardDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxExpenseDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CurrentFederalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit_bbeff925-a146-2078-8abf-f4cd97255735" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_CurrentFederalTaxExpenseBenefit_bbeff925-a146-2078-8abf-f4cd97255735" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_0a099f0c-8f61-7b47-fb6f-d9dfccab6a2b" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_0a099f0c-8f61-7b47-fb6f-d9dfccab6a2b" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2ac2b83b-7587-ac08-d667-af95bd01fbb2" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2ac2b83b-7587-ac08-d667-af95bd01fbb2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_01bd828d-ff2f-1258-4ecb-6afd711760b6" xlink:type="locator" />
    <calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_01bd828d-ff2f-1258-4ecb-6afd711760b6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CurrentForeignTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentForeignTaxExpenseBenefit_1be7a3a1-cbc3-8ffe-f157-edb51cd26a68" xlink:type="locator" />
    <calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_CurrentForeignTaxExpenseBenefit_1be7a3a1-cbc3-8ffe-f157-edb51cd26a68" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_de4150a6-31ba-55b3-12d4-35cb377c9ca2" xlink:type="locator" />
    <calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_b8dcf191-083d-828d-7b9f-e2d2969b89f4" xlink:to="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_de4150a6-31ba-55b3-12d4-35cb377c9ca2" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesTaxCreditCarryforwardsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesUnrecognizedTaxBenefitRollForwarddetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/IncomeTaxesValuationAllowanceDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/Investments" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsContractualMaturitiesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_9361d00b-bf28-09e2-175e-2f8c5c8d39ac" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_0c84ece3-1f8c-2bb3-6d4d-e7a215e4c9c1" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_9361d00b-bf28-09e2-175e-2f8c5c8d39ac" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_0c84ece3-1f8c-2bb3-6d4d-e7a215e4c9c1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_0936fe34-b1c6-5f4e-1eee-fa338ed8b930" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_9361d00b-bf28-09e2-175e-2f8c5c8d39ac" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_0936fe34-b1c6-5f4e-1eee-fa338ed8b930" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_a6e76a34-fa42-d66f-a2a4-5865ce92446b" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_465ba6e6-2b33-45fe-3e73-c5293643fc38" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecurities_a6e76a34-fa42-d66f-a2a4-5865ce92446b" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_465ba6e6-2b33-45fe-3e73-c5293643fc38" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_73b022da-9054-5e1b-96dd-04e339313a48" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecurities_a6e76a34-fa42-d66f-a2a4-5865ce92446b" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_73b022da-9054-5e1b-96dd-04e339313a48" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_fc1c6482-bc06-c49d-f5fe-3b9e6e37b9c3" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_23f4b68d-024f-b771-52d7-9c6fb8b84fd6" xlink:type="locator" />
    <calculationArc order="1" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_fc1c6482-bc06-c49d-f5fe-3b9e6e37b9c3" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_23f4b68d-024f-b771-52d7-9c6fb8b84fd6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_71eca22f-9f1c-f22f-4df6-b11a94d2b626" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_fc1c6482-bc06-c49d-f5fe-3b9e6e37b9c3" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_71eca22f-9f1c-f22f-4df6-b11a94d2b626" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_a6e76a34-fa42-d66f-a2a4-5865ce92446b" xlink:type="locator" />
    <calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_fc1c6482-bc06-c49d-f5fe-3b9e6e37b9c3" xlink:to="loc_us-gaap_AvailableForSaleSecurities_a6e76a34-fa42-d66f-a2a4-5865ce92446b" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/InvestmentsAvailableForSaleInvestmentsInUnrealizedLossPositionDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_c35590de-1283-217c-1e2d-b560ceb2d9d5" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_c2664d2a-d932-50de-cb13-d64c703c9cca" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_c35590de-1283-217c-1e2d-b560ceb2d9d5" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_c2664d2a-d932-50de-cb13-d64c703c9cca" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_b37a8bf4-dc04-a4ef-c09d-c513c2f150f4" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_c35590de-1283-217c-1e2d-b560ceb2d9d5" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_b37a8bf4-dc04-a4ef-c09d-c513c2f150f4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_71eca22f-9f1c-f22f-4df6-b11a94d2b626" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_425e9179-54fd-063e-1581-0b030674ccd1" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_71eca22f-9f1c-f22f-4df6-b11a94d2b626" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_425e9179-54fd-063e-1581-0b030674ccd1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_fc2b4e89-9ed0-4d1c-c7d6-28b029fbe54f" xlink:type="locator" />
    <calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_71eca22f-9f1c-f22f-4df6-b11a94d2b626" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_fc2b4e89-9ed0-4d1c-c7d6-28b029fbe54f" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/InvestmentsProceedsFromSalesOfInvestmentsDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/InvestmentsTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/LegalSettlement" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/LegalSettlementDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/LegalSettlementTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/NetIncomeLossPerShare" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareComputationOfBasicAndDilutedNetIncomeLossPerShareDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareScheduleOfAntidilutiveSecuritiesExcludedFromComputationDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/NetIncomeLossPerShareTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/PropertyAndEquipment" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/PropertyAndEquipmentDepreciationExpenseDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/PropertyAndEquipmentPropertyAndEquipmentByTypeDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_7ce178a4-245f-fa78-36a1-552609a67554" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_6591f040-08b3-69a1-a560-c70736475ada" xlink:type="locator" />
    <calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_7ce178a4-245f-fa78-36a1-552609a67554" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_6591f040-08b3-69a1-a560-c70736475ada" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_b84a1570-30ad-4e3a-2391-9767a64e15fd" xlink:type="locator" />
    <calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_7ce178a4-245f-fa78-36a1-552609a67554" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_b84a1570-30ad-4e3a-2391-9767a64e15fd" xlink:type="arc" />
  </calculationLink>
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/PropertyAndEquipmentTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SegmentInformation" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SegmentInformationRevenueByGeographicTheaterDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SegmentInformationRevenueFromExternalCustomersByProductsAndServicesDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SegmentInformationTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnaudited" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnauditedDetails" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/SelectedQuarterlyFinancialDataUnauditedTables" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/StockholdersEquity" xlink:type="extended" />
  <calculationLink xlink:role="http://www.paloaltonetworks.com/role/StockholdersEquitySecondaryOfferingDetails" xlink:type="extended" />
</linkbase>
