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  <xsd:element abstract="true" id="ftnt_DeiAbstract" name="DeiAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" 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 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 abstract="true" id="ftnt_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" 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_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_Expiringin2031Member" name="Expiringin2031Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_FinTecComputersMember" name="FinTecComputersMember" 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_IncomeTaxesPayableMember" name="IncomeTaxesPayableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_IncometaxExpenseBenefitDeferredTaxBenefitCanadianStockBasedCompensationExpense" name="IncometaxExpenseBenefitDeferredTaxBenefitCanadianStockBasedCompensationExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" 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 id="ftnt_InventoryFinishedGoodsNetofReservesHeldbyDistributors" name="InventoryFinishedGoodsNetofReservesHeldbyDistributors" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="ftnt_InventoryRawMaterialsNetofReservesatContractManufacturers" name="InventoryRawMaterialsNetofReservesatContractManufacturers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <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_LongTermInvestmentsLineItemMember" name="LongTermInvestmentsLineItemMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_LossContingencyAmortizationPeriodofCovenantNottoSue" name="LossContingencyAmortizationPeriodofCovenantNottoSue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" 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_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_NumberofPrivatelyHeldCompanies" name="NumberofPrivatelyHeldCompanies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <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_OtherEuropeMiddleEastandAfricanCountriesMember" name="OtherEuropeMiddleEastandAfricanCountriesMember" 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 id="ftnt_ProceedsfromLegalSettlementDeferred" name="ProceedsfromLegalSettlementDeferred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ProceedsfromLegalSettlementUsedtoOffsetContingentLegalFees" name="ProceedsfromLegalSettlementUsedtoOffsetContingentLegalFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ProductGrossProfit" name="ProductGrossProfit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ftnt_PurchasePriceOfCommonStockAsPercentageOfLowerOfFairMarketValueOfCommonStockOnFirstDayOfOfferingPeriodOrLastDayOfPurchasePeriod" name="PurchasePriceOfCommonStockAsPercentageOfLowerOfFairMarketValueOfCommonStockOnFirstDayOfOfferingPeriodOrLastDayOfPurchasePeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_Range15.28to19.94Member" name="Range15.28to19.94Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_Range2013To2396Member" name="Range2013To2396Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_Range26.49to26.70Member" name="Range26.49to26.70Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_Range31.39to33.31Member" name="Range31.39to33.31Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_Range38.73to48.83Member" name="Range38.73to48.83Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_Range843To899Member" name="Range843To899Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodTax" name="ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ReservedForFutureEsppIssuancesMember" name="ReservedForFutureEsppIssuancesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" 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 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_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 id="ftnt_ServicesGrossProfit" name="ServicesGrossProfit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesAxis" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesDomain" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesDomain" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximum" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximumPercent" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximumPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <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 id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedBeforeAdjustments" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedBeforeAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfFixedAmountOfSharesMember" name="ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfFixedAmountOfSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfOutstandingSharesOnLastDayOfPreceedingYearMember" name="ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfOutstandingSharesOnLastDayOfPreceedingYearMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareRepurchaseProgramMember" name="ShareRepurchaseProgramMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <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 abstract="true" id="ftnt_StockPlans2000and2008Member" name="StockPlans2000and2008Member" 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 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:schema>
