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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2018-08-04</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000788965</issuerCik>
        <issuerName>HALLADOR ENERGY CO</issuerName>
        <issuerTradingSymbol>HNRG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001032385</rptOwnerCik>
            <rptOwnerName>LUBAR DAVID J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>833 E. MICHIGAN STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1500</rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2788685</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through Lubar &amp; Co.</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These securities are owned by Lubar Equity Fund, LLC (&quot;LEF&quot;).  Lubar &amp; Co., Incorporated is the sole manager of the fund.  Mr. David Lubar, as a director and President of Lubar &amp; Co., may be deemed to share voting and dispositive power as to the shares held by LEF. Mr. David Lubar disclaims beneficial ownership in the shares owned by LEF, except to the extent of his respective pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>David J. Lubar</signatureName>
        <signatureDate>2018-08-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
