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

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-04-24</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001089104</issuerCik>
        <issuerName>QUEST OIL CORP</issuerName>
        <issuerTradingSymbol>QOIL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001339182</rptOwnerCik>
            <rptOwnerName>PHILLIPS CHRISTOPHER</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>580 SECOND STREET, SUITE 102</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ENCINITAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>47654</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Placement Agent Series A Warrant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.80</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-10-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-10-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>672291</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Midtown Partners &amp; Co. LLC</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Placement Agent Series B Warrant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.46</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-10-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-10-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>336145</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Midtown Partners &amp; Co. LLC</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Placement Agent Series C Warrant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.56</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-10-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2012-10-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>336145</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Midtown Partners &amp; Co. LLC</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Placement Agent Series D Warrant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.40</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-10-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-10-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>672291</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Midtown Partners &amp; Co. LLC</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series D Warrant</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>.22</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-05-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2011-05-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1000000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the 2006 Director's Annual Compensation Program (the &quot;Program&quot;) effective May 1, 2006 . Through the Program, each Director receives an award of $10,000 of the issuer's restricted stock at $0.22 per share every 90 days and a  common stock purchase warrant to purchase 1,000,000 shares of Quest Oil Corporation's restricted common stock at an exercise price of $0.22 per share. The warrants vest at a rate of 250,000 warrants every 90 days beginning the effective date of May 1, 2006. As of the date of this filing, Mr. Phillips has been awarded 45,454 shares of common stock pursuant to the Program.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Chris Phillips</signatureName>
        <signatureDate>2006-05-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
