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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 Tl/UPmh65TNJtbDcPRd9AQ==

<SEC-DOCUMENT>0001140361-10-024961.txt : 20100610
<SEC-HEADER>0001140361-10-024961.hdr.sgml : 20100610
<ACCEPTANCE-DATETIME>20100610102216
ACCESSION NUMBER:		0001140361-10-024961
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100609
FILED AS OF DATE:		20100610
DATE AS OF CHANGE:		20100610

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MANNING PATRICK T
		CENTRAL INDEX KEY:			0001205460

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31993
		FILM NUMBER:		10889238

	MAIL ADDRESS:	
		STREET 1:		20810 FERNBUSH LANE
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77073

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:		2751 CENTERVILLE RD.
		STREET 2:		SUITE 3131
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19803
		BUSINESS PHONE:		3024789170

	MAIL ADDRESS:	
		STREET 1:		20810 FERNBUSH LANE
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77073

	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>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-06-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001205460</rptOwnerCik>
            <rptOwnerName>MANNING PATRICK T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>20810 FERNBUSH LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77073</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-09</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>13.6851</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33557</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares were sold as a result of a margin call by the Reporting Person's broker.</footnote>
        <footnote id="F2">This is the weighted average price per share at which the shares were sold.  Shares were sold at prices ranging from $13.500 to $13.785 per share.  Upon request, the Reporting Person will provide to the staff of the SEC, to the issuer, or to a security holder the full information regarding the number of shares sold at each separate price.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Roger M. Barzun under a Power of Attorney</signatureName>
        <signatureDate>2010-06-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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