<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-07-01</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0001179929</issuerCik>
        <issuerName>MOLINA HEALTHCARE INC</issuerName>
        <issuerTradingSymbol>MOH</issuerTradingSymbol></issuer>
<reportingOwner>
<reportingOwnerId>
            <rptOwnerCik>0001246931</rptOwnerCik>
            <rptOwnerName>DENTINO WILLIAM</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>0</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>1</isOther>
<officerTitle></officerTitle>
<otherText>Trustee of 2 Trust Owners</otherText></reportingOwnerRelationship></reportingOwner>
<nonDerivativeSecurity>
<securityTitle>
<value>common stock</value></securityTitle>
<transactionDate>
<value>2003-07-01</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>J</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
<footnoteId id="F1"/></transactionCoding>
<transactionTimeliness>
<value></value></transactionTimeliness>
<transactionAmounts>
<transactionShares>
<value>1000</value></transactionShares>
<transactionValue>
<value>17.50</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>1000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity>
<footnotes>
<footnote id="F1">Purchase of shares in the Issuer&#x92;s directed share program in connection with its initial public offering.</footnote></footnotes>
<ownerSignature>
<signatureName>William Dentino, Co-Trustee, by Karen Calhoun, Attorney-In-Fact pursuant to Exhibit 24 hereto</signatureName>
<signatureDate>2003-07-03</signatureDate></ownerSignature></ownershipDocument>


