-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001140361-10-008509.txt : 20100225
<SEC-HEADER>0001140361-10-008509.hdr.sgml : 20100225
<ACCEPTANCE-DATETIME>20100225170243
ACCESSION NUMBER:		0001140361-10-008509
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100224
FILED AS OF DATE:		20100225
DATE AS OF CHANGE:		20100225

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CHEMBIO DIAGNOSTICS, INC.
		CENTRAL INDEX KEY:			0001092662
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				880425691
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3661 HORSEBLOCK ROAD
		CITY:			MEDFORD
		STATE:			NY
		ZIP:			11763
		BUSINESS PHONE:		(631) 924-1135

	MAIL ADDRESS:	
		STREET 1:		3661 HORSEBLOCK ROAD
		CITY:			MEDFORD
		STATE:			NY
		ZIP:			11763

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Chembio Diagnostics Inc.
		DATE OF NAME CHANGE:	20040607

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TRADING SOLUTIONS COM INC
		DATE OF NAME CHANGE:	19990805

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CRESTVIEW CAPITAL MASTER LLC
		CENTRAL INDEX KEY:			0001303225

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30379
		FILM NUMBER:		10634423

	BUSINESS ADDRESS:	
		STREET 1:		95 REVERE DRIVE
		STREET 2:		SUITE A
		CITY:			NORTHBROOK
		STATE:			IL
		ZIP:			60062
		BUSINESS PHONE:		847-559-0060

	MAIL ADDRESS:	
		STREET 1:		95 REVERE DRIVE
		STREET 2:		SUITE A
		CITY:			NORTHBROOK
		STATE:			IL
		ZIP:			60062

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Crestview Capital Partners, LLC
		CENTRAL INDEX KEY:			0001396338
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30379
		FILM NUMBER:		10634424

	BUSINESS ADDRESS:	
		STREET 1:		95 REVERE DRIVE, SUITE A
		CITY:			NORTHBROOK
		STATE:			IL
		ZIP:			60062
		BUSINESS PHONE:		847-559-0060

	MAIL ADDRESS:	
		STREET 1:		95 REVERE DRIVE, SUITE A
		CITY:			NORTHBROOK
		STATE:			IL
		ZIP:			60062
</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>2010-02-24</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001092662</issuerCik>
        <issuerName>CHEMBIO DIAGNOSTICS, INC.</issuerName>
        <issuerTradingSymbol>CEMI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001303225</rptOwnerCik>
            <rptOwnerName>CRESTVIEW CAPITAL MASTER LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>95 REVERE DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE A</rptOwnerStreet2>
            <rptOwnerCity>NORTHBROOK</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60062</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001396338</rptOwnerCik>
            <rptOwnerName>Crestview Capital Partners, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>95 REVERE DRIVE, SUITE A</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORTHBROOK</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60062</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $0.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-24</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18907431</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares of the Issuer's common stock, $0.01 par value per shares (&quot;Common Stock&quot; or the &quot;Shares&quot;) are held for the account of Crestview Capital Master, L.L.C. (&quot;Crestview Master&quot;), which is a Reporting Person.</footnote>
        <footnote id="F2">Crestview Capital Partners, L.L.C. (&quot;Crestview Partners&quot;) serves as the sole manager of Crestview Master, and as such has the power to vote and to direct the Shares owned by Crestview Master, and therefore may be deemed an indirect beneficial owner of the Shares held in the account of Crestview Master.</footnote>
        <footnote id="F3">Crestview Capital Fund III, L.P. (&quot;Crestview Fund III&quot;) and Crestview Capital Offshore Fund, Inc. (&quot;Crestview Offshore&quot;) are &quot;feeder funds&quot; which invest substantially all of their capital into Crestview Master.  As of February 24, 2010, Crestview Master is distributing all of the Shares that are currently held by Crestview Master to its equity holders (including Crestview Fund III and Crestview Offshore) on a pro rata basis based upon their respective interests in Crestview Master's net assets (the &quot;First Distribution&quot;).  As a result of the First Distribution, Crestview Fund III will receive 12,990,569 Shares (or 20.97% of the 61,944,901 total number of Shares outstanding) and Crestview Offshore will receive 3,356,040 (or 5.42% of the 61,944,901 total number of Shares outstanding) (in each case, the total Shares outstanding is based upon information provided by the Issuer in its recently filed quarterly report on Form 10-Q).</footnote>
        <footnote id="F4">Immediately upon receipt of its pro rata portion of the Shares currently held by Crestview Master, Crestview Fund III will be distributing its Shares to the Crestview Fund III partners, pro rata based upon each partner?s equity interest in Crestview Fund III (the &quot;Second Distribution,&quot; and together with the First Distribution, the &quot;Transaction&quot;).   As a result of the Transaction, Crestview Master and Crestview Fund III may be deemed to be the beneficial owner of 0 Shares.  The First and Second Distributions are two parts of the same overall Transaction with the same overall purpose.</footnote>
        <footnote id="F5">No consideration was paid by the equity holders for the Shares.</footnote>
        <footnote id="F6">Crestview Partners disclaims beneficial ownership within the meaning of Rule 16a-1(a)(2) under the Securities Exchange Act of 1934 (the &quot;Exchange Act&quot;) in the securities owned by Crestview Master except to the extent, if any, of their pecuniary interest therein.</footnote>
    </footnotes>

    <remarks>This Form 4 is also being filed to check the box indicating that the Reporting Person is no longer subject to Section 16.</remarks>

    <ownerSignature>
        <signatureName>Crestview Capital Master, L.L.C. By: Crestview Capital Partners, L.L.C., its sole Manager By: /s/ Daniel I. Warsh</signatureName>
        <signatureDate>2010-02-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Crestview Capital Partners, L.L.C. By: /s/ Daniel I. Warsh Name Daniel I. Warsh</signatureName>
        <signatureDate>2010-02-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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