<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-09-29</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000874761</issuerCik>
        <issuerName>AES CORPORATION</issuerName>
        <issuerTradingSymbol>aes</issuerTradingSymbol>
</issuer>
<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001237625</rptOwnerCik>
            <rptOwnerName>LURASCHI WILLIAM R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE AES CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>1001 N. 19TH STREET</rptOwnerStreet2>
            <rptOwnerCity>ARLINGTON</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22209</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Executive Vice President</officerTitle>
<otherText></otherText>
</reportingOwnerRelationship>
</reportingOwner>
<nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-09-29</value>
</transactionDate>
<deemedExecutionDate><value>2003-09-29</value>
</deemedExecutionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>13427</value>
</transactionShares>
<transactionPricePerShare><value>7.4595</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>39667</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership><value>by 401k</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
</nonDerivativeTable>
<derivativeTable></derivativeTable>
<footnotes></footnotes>
<ownerSignature><signatureName>William R. Luraschi</signatureName>
<signatureDate>2003-09-30</signatureDate>
</ownerSignature>
</ownershipDocument>

