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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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 t5oxu+LKBd1oHFbeShQf6Q==

<SEC-DOCUMENT>0001140361-08-012128.txt : 20080513
<SEC-HEADER>0001140361-08-012128.hdr.sgml : 20080513
<ACCEPTANCE-DATETIME>20080513125045
ACCESSION NUMBER:		0001140361-08-012128
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080513
FILED AS OF DATE:		20080513
DATE AS OF CHANGE:		20080513

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HEMSLEY MAARTEN D
		CENTRAL INDEX KEY:			0001018000

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31993
		FILM NUMBER:		08826607

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		7819342219

	MAIL ADDRESS:	
		STREET 1:		265 WASHINGTON ST
		CITY:			AUXBURY
		STATE:			MA
		ZIP:			02332
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-05-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001018000</rptOwnerCik>
            <rptOwnerName>HEMSLEY MAARTEN D</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>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-05-13</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2564</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>274488</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares were awarded to the reporting person by the Company and are subject to an agreement imposing restrictions and other conditions on their resale executed by the holder on May 13, 2008.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Roger M. Barzun under a power of attorney</signatureName>
        <signatureDate>2008-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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