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  <xsd:element abstract="true" id="ftnt_ConsolidatedStatementsOfComprehensiveIncomeAbstract" name="ConsolidatedStatementsOfComprehensiveIncomeAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_CostOfGoodsSoldMember" name="CostOfGoodsSoldMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_CostOfServicesMember" name="CostOfServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_CyberSponseInc.Member" name="CyberSponseInc.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_DebtSecuritiesAvailableforsaleContinuousUnrealizedLossPositionAbstract" name="DebtSecuritiesAvailableforsaleContinuousUnrealizedLossPositionAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_DeferredTaxAssetsOperatingLeaseLiabilities" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_DeferredTaxesLineItems" name="DeferredTaxesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_DefinedContributionPlanEmployerMatchingContributionAmount" name="DefinedContributionPlanEmployerMatchingContributionAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_DirectorsAndOtherServiceProvidersMember" name="DirectorsAndOtherServiceProvidersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_EarningsPerShareLineItems" name="EarningsPerShareLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EffectiveIncomeTaxRateReconciliationCanadianDeemedDividendDistribution" name="EffectiveIncomeTaxRateReconciliationCanadianDeemedDividendDistribution" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesAmount" name="EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017GlobalIntangibleLowTaxedIncomeAmount" name="EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017GlobalIntangibleLowTaxedIncomeAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017TaxBookBasisDifferenceAmount" name="EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017TaxBookBasisDifferenceAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_EmployeeMember" name="EmployeeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EmployeeStockPurchasePlanAnnualPurchaseLimit" name="EmployeeStockPurchasePlanAnnualPurchaseLimit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EmployeeStockPurchasePlanPeriodicPurchaseLimit" name="EmployeeStockPurchasePlanPeriodicPurchaseLimit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_EnSiloLtd.Member" name="EnSiloLtd.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_EquitySecuritiesWithoutReadilyDeterminableFairValueRealizedGainLoss" name="EquitySecuritiesWithoutReadilyDeterminableFairValueRealizedGainLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_EuropeMiddleEastAndAfricaMember" name="EuropeMiddleEastAndAfricaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_EvaluationUnitsMember" name="EvaluationUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ExclusiveNetworksGroupMember" name="ExclusiveNetworksGroupMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_FinancialInstrumentsAndFairValueAbstract" name="FinancialInstrumentsAndFairValueAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_HardwareProductWarrantyMember" name="HardwareProductWarrantyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_IncomeTaxBenefitFromStockOptionPlansTableTextBlock" name="IncomeTaxBenefitFromStockOptionPlansTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_IncomeTaxLiabilitiesNoncurrentMember" name="IncomeTaxLiabilitiesNoncurrentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_IndividualOwning10PercentOrLessOfStockMember" name="IndividualOwning10PercentOrLessOfStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_IndividualOwning10PercentOrMoreOfStockMember" name="IndividualOwning10PercentOrMoreOfStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_IngramMicroMember" name="IngramMicroMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_InvestmentsClassificationAsLongTermMinimumMaturity" name="InvestmentsClassificationAsLongTermMinimumMaturity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_InvestmentsClassificationAsShortTermMaximumOriginalMaturity" name="InvestmentsClassificationAsShortTermMaximumOriginalMaturity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_InvestmentsClassificationAsShortTermMinimumOriginalMaturity" name="InvestmentsClassificationAsShortTermMinimumOriginalMaturity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_LeaseLiabilitiesArisingfromObtainingRightofUseAssetsAbstract" name="LeaseLiabilitiesArisingfromObtainingRightofUseAssetsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_LongTermInvestmentsLineItemMember" name="LongTermInvestmentsLineItemMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_MeruNetworksInc.Member" name="MeruNetworksInc.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_MoneyMarketFundsExcludingCommercialPaperMember" name="MoneyMarketFundsExcludingCommercialPaperMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_MutualCovenantNottoSueAgreementPatentClaimsExtensionOptionAdditionalProceeds" name="MutualCovenantNottoSueAgreementPatentClaimsExtensionOptionAdditionalProceeds" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_MutualCovenantNottoSueAgreementPatentClaimsExtensionOptionTerm" name="MutualCovenantNottoSueAgreementPatentClaimsExtensionOptionTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_MutualCovenantNottoSueAgreementPatentClaimsInitialTerm" name="MutualCovenantNottoSueAgreementPatentClaimsInitialTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_MutualCovenantNottoSueAgreementPatentClaimsTotalProceedsExpectedIfExtensionOptionUtilized" name="MutualCovenantNottoSueAgreementPatentClaimsTotalProceedsExpectedIfExtensionOptionUtilized" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_NumberOfBusinessActivities" name="NumberOfBusinessActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_NumberOfSegmentManagersResponsibleForOperations" name="NumberOfSegmentManagersResponsibleForOperations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_OperatingLeaseLeaseNotyetCommencedExpense" name="OperatingLeaseLeaseNotyetCommencedExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_OperatingLeaseRemainingLeaseTerm" name="OperatingLeaseRemainingLeaseTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_OtherAmericasMember" name="OtherAmericasMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_PerformanceShareWeightedAverageAssumptionsAbstract" name="PerformanceShareWeightedAverageAssumptionsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_PresentationAndPreparationOfConsolidatedFinancialStatementsPolicyTextBlock" name="PresentationAndPreparationOfConsolidatedFinancialStatementsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_PriceRangeFourMember" name="PriceRangeFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_PriceRangeOneMember" name="PriceRangeOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_PriceRangeThreeMember" name="PriceRangeThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_PriceRangeTwoMember" name="PriceRangeTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ProceedsFromMutualCovenantNottoSueAgreement" name="ProceedsFromMutualCovenantNottoSueAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ProceedsfromSaleofEquitySecuritiesWithoutReadilyDeterminableFairValue" name="ProceedsfromSaleofEquitySecuritiesWithoutReadilyDeterminableFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_PurchasePriceOfCommonStockAsPercentageOfLowerOfFairMarketValueOfCommonStockOnFirstDayOfOfferingPeriodOrLastDayOfPurchasePeriod" name="PurchasePriceOfCommonStockAsPercentageOfLowerOfFairMarketValueOfCommonStockOnFirstDayOfOfferingPeriodOrLastDayOfPurchasePeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodTax" name="ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_RepurchaseofCommonStockLiabilitiesIncurred" name="RepurchaseofCommonStockLiabilitiesIncurred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_RepurchaseofCommonStockSettlementofLiabilitiesIncurred" name="RepurchaseofCommonStockSettlementofLiabilitiesIncurred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ReservedForFutureOptionRestrictedStockUnitAndOtherEquityAwardGrantsMember" name="ReservedForFutureOptionRestrictedStockUnitAndOtherEquityAwardGrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_RevenueRecognitionPeriod" name="RevenueRecognitionPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_RevenuefromContractwithCustomersGeneralInvoicePayablePeriod" name="RevenuefromContractwithCustomersGeneralInvoicePayablePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_SalesCommissionsMember" name="SalesCommissionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_SalesRevenueMember" name="SalesRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleOfAmortizedCostsUnrealizedGainsAndLossesAndFairValueOfAvailableForSaleSecuritiesTableTextBlock" name="ScheduleOfAmortizedCostsUnrealizedGainsAndLossesAndFairValueOfAvailableForSaleSecuritiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ScheduleOfDeferredTaxesTable" name="ScheduleOfDeferredTaxesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ScheduleOfEarningsPerShareTable" name="ScheduleOfEarningsPerShareTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" name="ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" name="ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ScheduleOfWarrantiesTable" name="ScheduleOfWarrantiesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofEmployeeServiceSharebasedCompensationAllocationofRecognizedPeriodCostsbyAwardTypeTableTextBlock" name="ScheduleofEmployeeServiceSharebasedCompensationAllocationofRecognizedPeriodCostsbyAwardTypeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofEstimatedUsefulLivesofPropertyPlantandEquipmentTableTextBlock" name="ScheduleofEstimatedUsefulLivesofPropertyPlantandEquipmentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofFiniteLivedandIndefiniteLivedIntangibleAssetsTableTextBlock" name="ScheduleofFiniteLivedandIndefiniteLivedIntangibleAssetsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofSharebasedCompensationSharesWithheldforTaxesTableTextBlock" name="ScheduleofSharebasedCompensationSharesWithheldforTaxesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofSharebasedCompensationStockOptionsActivityAdditionalInformationTableTextBlock" name="ScheduleofSharebasedCompensationStockOptionsActivityAdditionalInformationTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleofSharebasedPaymentAwardEmployeeStockPurchasePlanAdditionalInformationTableTextBlock" name="ScheduleofSharebasedPaymentAwardEmployeeStockPurchasePlanAdditionalInformationTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_SecuritySubscriptionMember" name="SecuritySubscriptionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsIssuedWeightedAveragePricePerShare" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsIssuedWeightedAveragePricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExericsePriceAsPercentOfFairValueOnGrantDate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExericsePriceAsPercentOfFairValueOnGrantDate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_ShareRepurchaseProgramMember" name="ShareRepurchaseProgramMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" name="SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofSharesDeregistered" name="SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofSharesDeregistered" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_ShortTermInvestmentsLineItemMember" name="ShortTermInvestmentsLineItemMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_SoftwareProductWarrantyMember" name="SoftwareProductWarrantyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StateJurisdictionCaliforniaMember" name="StateJurisdictionCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_StockIssuedDuringPeriodSharesEquityIncentivePlans" name="StockIssuedDuringPeriodSharesEquityIncentivePlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" name="StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockOptionsAndRestrictedStockUnitsOutstandingMember" name="StockOptionsAndRestrictedStockUnitsOutstandingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockOptionsNonqualifyingMember" name="StockOptionsNonqualifyingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockPlan2009Member" name="StockPlan2009Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_StockRepurchaseProgramAdditionalAuthorizedAmount" name="StockRepurchaseProgramAdditionalAuthorizedAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_TechnicalSupportMember" name="TechnicalSupportMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_TransfersofEvaluationUnitsfromInventorytoPropertyandEquipment" name="TransfersofEvaluationUnitsfromInventorytoPropertyandEquipment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_WarrantiesLineItems" name="WarrantiesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_WarrantyLength" name="WarrantyLength" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ZoneFoxHoldingsLimitedMember" name="ZoneFoxHoldingsLimitedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
