<?xml version="1.0"?>

<ownershipDocument>

    <documentType>4</documentType>

    <periodOfReport>2003-06-06</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874691</issuerCik>
        <issuerName>OUTBACK STEAKHOUSE INC</issuerName>
        <issuerTradingSymbol>OSI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001044541</rptOwnerCik>
            <rptOwnerName>WILT TOBY S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeSecurity>
        <securityTitle>
            <value>Phantom Stock Units (&quot;PSU&quot;)</value>
        </securityTitle>
        <conversionOrExercisePrice>
            <value>0</value>
            <footnoteId id="F1"/>
        </conversionOrExercisePrice>
        <transactionDate>
            <value>2003-06-06</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>A</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>9.12</value>
                <footnoteId id="F2"/>
            </transactionShares>
            <transactionValue>
                <value>33.82</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>A</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <exerciseDate>
            <value>1988-08-08</value>
            <footnoteId id="F3"/>
        </exerciseDate>
        <expirationDate>
            <value>1988-08-08</value>
            <footnoteId id="F3"/>
        </expirationDate>
        <underlyingSecurity>
            <underlyingSecurityTitle>
                <value>Common Stock</value>
            </underlyingSecurityTitle>
            <underlyingSecurityShares>
                <value>9.12</value>
            </underlyingSecurityShares>
        </underlyingSecurity>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>2579.71</value>
                <footnoteId id="F4"/>
                <footnoteId id="F5"/>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </derivativeSecurity>

    <footnotes>
        <footnote id="F1">The security converts to common stock on a one-to-one basis.</footnote>
        <footnote id="F2">Shares reflect acquisition of additional PSU per reinvestment of dividends under the Company's Plan.</footnote>
        <footnote id="F3">The date provided is a &quot;dummy date&quot; used pursuant to instructions from SEC staff. The PSU were accrued under the Company's Deferred Compensation and Stock Plan (&quot;Plan&quot;) and are settled 100% in the Company's common stock upon cessation as a director.</footnote>
        <footnote id="F4">Derivative securities beneficially owned at end of year include: (i) 568.70 PSU accrued in 1997 at prices ranging from $15.840 to $17.669, and are each settled 100% in the Company's common stock on January 1, 2007; (ii) 416.68 PSU accrued in 1998 at prices ranging from $18.070 to $24.697, and are each settled 100% in the Company's common stock on January 1, 2007; (iii) 336.37 PSU accrued in 1999 at prices ranging from $25.33 to $36.68, and are each settled 100% in the Company's common stock on January 1, 2009; (iv) 378.49 PSU accrued in 2000 at prices ranging from $23.603 to $29.821, and are each settled 100% in the Company's common stock upon cessation as a director; (v) 374.41 PSU accrued in 2001 at prices ranging from $24.85 to $27.98, and are each settled 100% in the Company's common stock upon cessation as a director; [continued in footnote 5]</footnote>
        <footnote id="F5">[continued from footnote 4] (vi) 333.57 PSU accrued in 2002 at prices ranging from $28.00 to $37.38, and are each settled 100% in the Company's common stock upon cessation as a director; and (vii) 162.38 PSU accrued in 2003 at prices ranging from $33.82 to $34.54, and are each settled 100% in the Company's common stock upon cessation as a director.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Joseph J. Kadow, Attorney-in-Fact</signatureName>
        <signatureDate>2003-06-10</signatureDate>
    </ownerSignature>

</ownershipDocument>

