<SEC-DOCUMENT>0001769254-21-000002.txt : 20210223
<SEC-HEADER>0001769254-21-000002.hdr.sgml : 20210223
<ACCEPTANCE-DATETIME>20210223163730
ACCESSION NUMBER:		0001769254-21-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210219
FILED AS OF DATE:		20210223
DATE AS OF CHANGE:		20210223

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			McManus Geraldine
		CENTRAL INDEX KEY:			0001769254

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36583
		FILM NUMBER:		21666150

	MAIL ADDRESS:	
		STREET 1:		32000 AURORA ROAD
		STREET 2:		SUITE B
		CITY:			SOLON
		STATE:			OH
		ZIP:			44139

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENERGY FOCUS, INC/DE
		CENTRAL INDEX KEY:			0000924168
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC LIGHTING & WIRING EQUIPMENT [3640]
		IRS NUMBER:				943021850
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		32000 AURORA ROAD
		STREET 2:		SUITE B
		CITY:			SOLON
		STATE:			OH
		ZIP:			44139
		BUSINESS PHONE:		4407151300

	MAIL ADDRESS:	
		STREET 1:		32000 AURORA ROAD
		STREET 2:		SUITE B
		CITY:			SOLON
		STATE:			OH
		ZIP:			44139

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIBERSTARS INC /CA/
		DATE OF NAME CHANGE:	19940527
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161411622120978.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-02-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000924168</issuerCik>
        <issuerName>ENERGY FOCUS, INC/DE</issuerName>
        <issuerTradingSymbol>EFOI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001769254</rptOwnerCik>
            <rptOwnerName>McManus Geraldine</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>32000 AURORA ROAD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE B</rptOwnerStreet2>
            <rptOwnerCity>SOLON</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44139</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-02-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Restricted Stock Unit represents a contingent right to receive one share of Energy Focus, Inc. Common Stock.</footnote>
        <footnote id="F2">The Restricted Stock Units fully vest on the earlier of (i) the one year anniversary of the grant date or (ii) the date of the Company's annual meeting of stockholders next following the grant date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Tod A. Nestor, as Attorney-in-Fact</signatureName>
        <signatureDate>2021-02-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
