<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-09-05</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001019444</rptOwnerCik>
            <rptOwnerName>BRIDGES CHARLES HOWARD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2202 NORTH WEST SHORE BLVD</rptOwnerStreet1>
            <rptOwnerStreet2>5TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>TAMPA</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33607</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $.01</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>325</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

    </nonDerivativeTable>

    <derivativeTable>

        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units (&quot;PSU&quot;)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2003-09-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2.45</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>37.77</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2.45</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>774.81</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>

    </derivativeTable>

    <footnotes>
        <footnote id="F1">Of which 200 shares are owned by the Amended and Restated Revocable Trust Agreement of Helen H. Bridges under trust dated November 22, 1999, as amended (the &quot;Spouse Trust&quot;), to which Mrs. Bridges is the sole Trustee and beneficiary of the Spouse Trust. The reporting person continues to report beneficial ownership of all of the shares held by the Spouse Trust.</footnote>
        <footnote id="F2">Of which 125 shares are owned by the Amended and Restated Revocable Trust Agreement of Charles H. Bridges under trust dated November 22, 1999, as amended (the &quot;Trust&quot;),  to which the reporting person is the sole Trustee and beneficiary of the Trust. The reporting person continues to report beneficial ownership of all of the shares held by the Trust.</footnote>
        <footnote id="F3">The security converts to common stock on a one-to-one basis.</footnote>
        <footnote id="F4">Shares reflect acquisition of additional PSU per reinvestment of dividends under the Company's Plan.</footnote>
        <footnote id="F5">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 on December 31, 2003.</footnote>
        <footnote id="F6">Derivative securities beneficially owned at end of reporting period include: (i) 440.63 PSU accrued in 2002 at prices ranging from $28.00 to $37.38, and are each settled 100% in the Company's common stock on December 31, 2003; and (ii) 331.73 PSU accrued in 2003 at prices ranging from $33.82 to $37.77, and are each settled 100% in the Company's common stock on December 31, 2003.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Joseph J. Kadow, Attorney-in-Fact</signatureName>
        <signatureDate>2003-09-05</signatureDate>
    </ownerSignature>

</ownershipDocument>

