-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 DsnRIJqDSkdF/ieIrhQTfPLAE4to2Jga7n+etACCs5saZXvHRJkMOpam6oRbSBw2
 ay9xWdkqpLMAq9kLLR+r6w==

<SEC-DOCUMENT>0001042046-03-000221.txt : 20031208
<SEC-HEADER>0001042046-03-000221.hdr.sgml : 20031208
<ACCEPTANCE-DATETIME>20031208114059
ACCESSION NUMBER:		0001042046-03-000221
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031205
FILED AS OF DATE:		20031208

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MISCHELL THOMAS E
		CENTRAL INDEX KEY:			0001185853

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13653
		FILM NUMBER:		031041848

	BUSINESS ADDRESS:	
		STREET 1:		ONE EAST FOURTH STREET
		STREET 2:		SUITE 919
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45202
		BUSINESS PHONE:		5135792540

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMERICAN FINANCIAL GROUP INC
		CENTRAL INDEX KEY:			0001042046
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				311544320
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE EAST FOURTH STREET
		STREET 2:		SUITE 919
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45202
		BUSINESS PHONE:		5135792121

	MAIL ADDRESS:	
		STREET 1:		ONE EAST FOURTH STREET
		STREET 2:		SUITE 919
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45202

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AMERICAN FINANCIAL GROUP HOLDINGS INC
		DATE OF NAME CHANGE:	19970709
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-12-05</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001042046</issuerCik>
        <issuerName>AMERICAN FINANCIAL GROUP INC</issuerName>
        <issuerTradingSymbol>AFG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185853</rptOwnerCik>
            <rptOwnerName>MISCHELL THOMAS E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE EAST FOURTH STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CINCINNATI</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President - Taxes</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2003-12-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>17781</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>22.74</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>102503</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>#1</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>300</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>#2</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7928144</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>#3</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>400.61</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>#4</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares were acquired as merger consideration in the Merger between the issuer and its former subsidiary American Financial Corporation.</footnote>
        <footnote id="F2">Indirect #1:  Represents one-half of the 2,000 shares held by a general partnership of which the Reporting Person is a 50% partner.</footnote>
        <footnote id="F3">Indirect #2:  Held by a minor child of the Reporting Person</footnote>
        <footnote id="F4">Indirect #3:  These shares are held by the American Financial Group, Inc. Retirement and Savings Plan (&quot;RASP&quot;) for which the Reporting Person acts as a Trustee with voting and dispositive power.  The Reporting Person has no direct pecuniary interest in any shares of Common Stock held by the RASP.</footnote>
        <footnote id="F5">Indirect #4:  The number of shares of Common Stock which would be represented by the value of the Reporting Person's common stock fund account in the Issuer's Retirement and Savings Plan (&quot;401(k) Plan&quot;), based on a 401(k) Plan statement as of 12/31/02.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Karl J. Grafe, as Attorney-in-Fact for Thomas E. Mischell</signatureName>
        <signatureDate>2003-12-08</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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