<SEC-DOCUMENT>0000874238-19-000126.txt : 20191029
<SEC-HEADER>0000874238-19-000126.hdr.sgml : 20191029
<ACCEPTANCE-DATETIME>20191029143628
ACCESSION NUMBER:		0000874238-19-000126
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20191027
FILED AS OF DATE:		20191029
DATE AS OF CHANGE:		20191029

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Chandler Richard E Jr
		CENTRAL INDEX KEY:			0001348163

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31993
		FILM NUMBER:		191175959

	MAIL ADDRESS:	
		STREET 1:		1800 HUGHES LANDING BLVD
		STREET 2:		SUITE 250
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77380

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STERLING CONSTRUCTION CO INC
		CENTRAL INDEX KEY:			0000874238
		STANDARD INDUSTRIAL CLASSIFICATION:	HEAVY CONSTRUCTION OTHER THAN BUILDING CONST - CONTRACTORS [1600]
		IRS NUMBER:				251655321
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1800 HUGHES LANDING BLVD.
		STREET 2:		SUITE 250
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77380
		BUSINESS PHONE:		281-214-0800

	MAIL ADDRESS:	
		STREET 1:		1800 HUGHES LANDING BLVD.
		STREET 2:		SUITE 250
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77380

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OAKHURST CO INC
		DATE OF NAME CHANGE:	19950831

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OAKHURST CAPITAL INC
		DATE OF NAME CHANGE:	19931130
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_157237415844415.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-10-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874238</issuerCik>
        <issuerName>STERLING CONSTRUCTION CO INC</issuerName>
        <issuerTradingSymbol>STRL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001348163</rptOwnerCik>
            <rptOwnerName>Chandler Richard E Jr</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1800 HUGHES LANDING BLVD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 250</rptOwnerStreet2>
            <rptOwnerCity>THE WOODLANDS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77380</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, General Counsel &amp; Sec</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-10-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2029</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.87</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46017</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares were part of a restricted stock award, made pursuant to the Company's Stock Incentive Plan, a portion of which was released on October 27, 2019. The shares were retained by the Company at the election of the Reporting Person pursuant to a procedure approved by the Board of Directors to satisfy the Company's tax withholding requirements, based on the closing price of the Company's common stock on the release date as permitted by the Plan.</footnote>
        <footnote id="F2">Of these shares, 29,458 shares are subject to restrictions on their sale or other transfer and to forfeiture under certain circumstances.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Craig B. Allen (under Power of Attorney)</signatureName>
        <signatureDate>2019-10-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
