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

    <schemaVersion>X0202</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2004-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000854560</issuerCik>
        <issuerName>GREAT SOUTHERN BANCORP INC</issuerName>
        <issuerTradingSymbol>GSBC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001179760</rptOwnerCik>
            <rptOwnerName>BROWN JULIE A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1451 E BATTLEFIELD</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 9009</rptOwnerStreet2>
            <rptOwnerCity>SPRINGFIELD</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>65808</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</value>
            </securityTitle>
            <transactionCoding>
                <transactionFormType></transactionFormType>
            </transactionCoding>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6863</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-09-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>7752</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>369738</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Turner Family LTD Partnership</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Option to purchase</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>20.815</value>
            </conversionOrExercisePrice>
            <transactionCoding>
                <transactionFormType></transactionFormType>
            </transactionCoding>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-08-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Turner Family Limited Partnership (the &quot;Partnership&quot;) continues to own the same number of shares (1,566,024) as it did immediately prior to this transaction.  The transaction reflects an exchange (the &quot;Exchange&quot;) of partnership units in the Partnership for estate planning purposes involving the reporting person, Julie A. Brown, and her brother, Joseph W. Turner, President and CEO and a director of the issuer, and their parents, William V. Turner, Chairman of the Board of Directors of the issuer, and Ann S. Turner.  Although, as a result of the Exchange, Julie Brown and Joseph Turner replaced William and Ann Turner as general partners, each family member's share of the Partnership's capital account and profits did not substantially change and their economic interest in the shares of the issuer's common stock held by the Partnership were not significantly affected by the Exchange. (continued in Footnote 2 below)</footnote>
        <footnote id="F2">(continued from Footnote 1) Prior to the Exchange, as limited partners of the Partnership, Julie Brown and Joseph Turner were not, for purposes of Section 16 of the Securities Exchange Act of 1934 (the &quot;1934 Act&quot;), deemed to beneficially own any of the 1,566,024 shares of the issuer's common stock held by the Partnership.  Pursuant to the exchange agreement, each of Julie Brown and Joseph Turner obtained 400 general partnership units in exchange for 548 limited partnership units and each of William and Ann Turner obtained 548 limited partnership units in exchange for all 400 of their respective general partnership units.  (continued in Footnote 3 below)</footnote>
        <footnote id="F3">(continued from Footnote 2) As a result of the Exchange, for purposes of Section 16 of the 1934 Act, Julie Brown and Joseph Turner are now each deemed to beneficially own 23.61% of the 1,566,024 shares of the issuer's common stock held by the Partnership.  This reflects their respective shares of the Partnership's capital account represented by their general partnership units and remaining limited partnership units, as well as the limited partnership units held by trusts established for the benefit of their children, who reside in their households.</footnote>
        <footnote id="F4">2,500 shares vest on 8/20/2005
2,500 shares vest on 8/20/2006
2,500 shares vest on 8/20/2007
2,500 shares vest on 8/20/2008</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Matt Snyder, Attorney-in-fact for Julie A. Brown</signatureName>
        <signatureDate>2005-02-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
