<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-06-26</periodOfReport>

    <issuer>
        <issuerCik>0000910521</issuerCik>
        <issuerName>DECKERS OUTDOOR CORP</issuerName>
        <issuerTradingSymbol>DECK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001677396</rptOwnerCik>
            <rptOwnerName>O'Donnell Andrea</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>250 COROMAR DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GOLETA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>93117</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>President, Fashion Lifestyle</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </securityTitle>
            <transactionDate>
                <value>2019-06-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1842</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16630</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F2"/>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2019-06-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>570</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The Performance Based RSUs were granted pursuant to the Issuers 2015 Stock Incentive Plan.  The Performance Based RSUs may vest subject to the Issuers achievement of a pre established Earnings Per Share target for the fiscal year ending March 31, 2020. If the performance target is met, the Performance Based RSU will then vest as to 33.33 percent of the underlying shares on 8/15/2020, 33.33 percent on 8/15/2021, and 33.34 percent on 8/15/2022. If the performance target is not met, no vesting will occur and the Performance Based RSUs will be cancelled. The Performance Based RSUs will be settled in the Issuers common stock upon satisfaction of the vesting conditions.</footnote>
        <footnote id="F2">The Time Based RSUs were granted pursuant to the Issuers 2015 Stock Incentive Plan.  The Time Based RSUs vest as to 33.33 percent of the underlying shares on 8/15/2020, 33.33 percent on 8/15/2021, and 33.34 percent on 8/15/2022, subject to the satisfaction of continuous service requirements.  At the time that continuous service requirements cease to be met, no further vesting will occur and the remaining Time Based RSUs will not be earned.  The Time Based RSUs will be settled in the Issuers common stock upon satisfaction of the vesting conditions.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Lisa Bereda for Andrea O'Donnell as Attorney in Fact</signatureName>
        <signatureDate>2019-06-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
