-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 RdNtC8r+A18Q9CgRQEwX+e9VWJV1MwzCmC9YrQpLOwSJAQVL74ewDQ0MMqVeo7lI
 cEaxeDFvw3ZgpYOhPaetDA==

<SEC-DOCUMENT>0001179110-08-017919.txt : 20081007
<SEC-HEADER>0001179110-08-017919.hdr.sgml : 20081007
<ACCEPTANCE-DATETIME>20081007165222
ACCESSION NUMBER:		0001179110-08-017919
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20081006
FILED AS OF DATE:		20081007
DATE AS OF CHANGE:		20081007

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AES CORP
		CENTRAL INDEX KEY:			0000874761
		STANDARD INDUSTRIAL CLASSIFICATION:	COGENERATION SERVICES & SMALL POWER PRODUCERS [4991]
		IRS NUMBER:				541163725
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4300 WILSON BOULEVARD
		CITY:			ARLINGTON
		STATE:			VA
		ZIP:			22203
		BUSINESS PHONE:		7035221315

	MAIL ADDRESS:	
		STREET 1:		4300 WILSON BOULEVARD
		CITY:			ARLINGTON
		STATE:			VA
		ZIP:			22203

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AES CORPORATION
		DATE OF NAME CHANGE:	19930328

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KOSKINEN JOHN A
		CENTRAL INDEX KEY:			0001284783

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12291
		FILM NUMBER:		081112633

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		7033581315

	MAIL ADDRESS:	
		STREET 1:		C/O AES INC
		STREET 2:		1001 N. 19TH ST
		CITY:			ARLINGTON
		STATE:			VA
		ZIP:			22209
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-10-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874761</issuerCik>
        <issuerName>AES CORP</issuerName>
        <issuerTradingSymbol>AES</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001284783</rptOwnerCik>
            <rptOwnerName>KOSKINEN JOHN A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE AES CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>4300 WILSON BOULEVARD</rptOwnerStreet2>
            <rptOwnerCity>ARLINGTON</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22209</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-10-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.89</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by IRA</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>John A. Koskinen</signatureName>
        <signatureDate>2008-10-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----