<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-04-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001006384</issuerCik>
        <issuerName>NEVSTAR CORP</issuerName>
        <issuerTradingSymbol>nvsc.ob</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001431786</rptOwnerCik>
            <rptOwnerName>Song Lihui</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>123 CHUANGYE ROAD, HAIZHOU DISTRICT</rptOwnerStreet1>
            <rptOwnerStreet2>LIAONING PROVINCE</rptOwnerStreet2>
            <rptOwnerCity>FUXIN CITY</rptOwnerCity>
            <rptOwnerState>F4</rptOwnerState>
            <rptOwnerZipCode>123000</rptOwnerZipCode>
            <rptOwnerStateDescription>CHINA</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, CEO and chairman</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, .01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3472222</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15438612</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By spouse</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reported securities are held by Money Victory Limited, a British Virgin Islands corporation (&quot;Money Victory&quot;), of which the reporting person's wife Lin Tan was sole owner. On April 9, 2008, Lin Tan sold a 22.49% interest in Money Victory to Wonder Auto Limited, a British Virgin Islands corporation, for an aggregate purchase price of $5,000,000.  The purchase agreement between Lin Tan and Wonder Auto Limited provides that Wonder Auto Limited cannot receive shares of Nevstar stock until such time that such shares may be transferred to Wonder Auto Limited consistent with applicable U.S. securities law. Lin Tan is under contractual obligations to lend the $5,000,000 to Nevstar's BVI and Chinese subsidiaries as working capital within 30 days after the execution of the agreement. The reporting person disclaims beneficial ownership of the Nevstar common stock held by Money Victory except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Lihui Song</signatureName>
        <signatureDate>2008-04-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
