-----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,
 N0rrCprYSW6SU3UdFL9/6h6NWPeEqEafUlJg8D9G+TWpj9EBIilmB62B+RfuIKo2
 WGYPCx4diLRPWVJL0bzy9g==

<SEC-DOCUMENT>0000101778-08-000026.txt : 20080104
<SEC-HEADER>0000101778-08-000026.hdr.sgml : 20080104
<ACCEPTANCE-DATETIME>20080104172934
ACCESSION NUMBER:		0000101778-08-000026
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080102
FILED AS OF DATE:		20080104
DATE AS OF CHANGE:		20080104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARATHON OIL CORP
		CENTRAL INDEX KEY:			0000101778
		STANDARD INDUSTRIAL CLASSIFICATION:	PETROLEUM REFINING [2911]
		IRS NUMBER:				250996816
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1207

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 3128
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77253-3128
		BUSINESS PHONE:		7136296600

	MAIL ADDRESS:	
		STREET 1:		5555 SAN FELIPE ROAD
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	USX CORP
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	UNITED STATES STEEL CORP/DE
		DATE OF NAME CHANGE:	19860714

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SCHOFIELD SETH E
		CENTRAL INDEX KEY:			0001229768

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05153
		FILM NUMBER:		08512949

	BUSINESS ADDRESS:	
		STREET 1:		CALGON CARBON CORP
		STREET 2:		PO BOX 717
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15230-0717
		BUSINESS PHONE:		4127876786
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-01-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000101778</issuerCik>
        <issuerName>MARATHON OIL CORP</issuerName>
        <issuerTradingSymbol>MRO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001229768</rptOwnerCik>
            <rptOwnerName>SCHOFIELD SETH E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MARATHON OIL CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>5555 SAN FELIPE ROAD</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77056</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2035.831</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>61.40</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>44843.021</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Annual Non-Retainer Common Stock Award granted under Marathon Oil Corporation 2007 Incentive Compensation Plan. The annual non-retainer stock-based compensation represented by these common stock units are credited to an unfunded account and are payable in shares of common stock upon reporting person's retirement from the Board of Directors.</footnote>
        <footnote id="F2">Includes dividends of 523.48 shares previously not reported pursuant to Rule 16a-11.</footnote>
        <footnote id="F3">On June 18, 2007, the common stock of Marathon Oil Corporation split 2-for-1 for holders of record on May 23, 2007, resulting in the reporting person's ownership, in the aggregate, of 21225.48 additional shares of common stock or common stock units.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>W. F. Schwind, Jr., Attorney-in-Fact for Seth E. Schofield</signatureName>
        <signatureDate>2008-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----