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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-06-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001107601</issuerCik>
        <issuerName>ATHEROGENICS INC</issuerName>
        <issuerTradingSymbol>AGIX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001054828</rptOwnerCik>
            <rptOwnerName>ATTICUS CAPITAL LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>152 WEST 57TH STREET</rptOwnerStreet1>
            <rptOwnerStreet2>45TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001039546</rptOwnerCik>
            <rptOwnerName>BARAKETT TIMOTHY R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>152 WEST 57TH STREET</rptOwnerStreet1>
            <rptOwnerStreet2>45TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-06-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.32</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3915700</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Note</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Mr. Barakett, who is an additional Reporting Person, is the Chairman, Chief Executive Officer, and Managing Member of Atticus Capital, L.L.C., a Delaware limited liability company (&quot;Atticus Capital&quot;).  Atticus Capital and certain of its affiliated entities (collectively, the &quot;Atticus Entities&quot;) act as advisers for various investment funds (the &quot;Funds&quot;) and managed accounts (the &quot;Accounts&quot;).  Based on his relationship with the Atticus Entities, Mr. Barakett is deemed to be a beneficial owner of the Securities owned by the Funds and the Accounts for purposes of Rule 16a-1(a)(1) under the Securities Exchange Act of 1934.  Mr. Barakett and Atticus Capital disclaim beneficial ownership within the meaning of Rule 16a-1(a)(2) under the Securities Exchange Act of 1934 in the Securities owned by the Funds and the Accounts except to the extent, if any, of their pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Atticus Capital, L.L.C., by Timothy R. Barakett, Managing Member, by Nandita Hogan, attorney-in-fact</signatureName>
        <signatureDate>2005-06-16</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Timothy R. Barakett, by Nandita Hogan, attorney-in-fact</signatureName>
        <signatureDate>2005-06-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
