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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001293462-08-000012.txt : 20080519
<SEC-HEADER>0001293462-08-000012.hdr.sgml : 20080519
<ACCEPTANCE-DATETIME>20080519160340
ACCESSION NUMBER:		0001293462-08-000012
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080515
FILED AS OF DATE:		20080519
DATE AS OF CHANGE:		20080519

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:			Siebert Lawrence A.
		CENTRAL INDEX KEY:			0001291343

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30379
		FILM NUMBER:		08845296

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		631-924-1135

	MAIL ADDRESS:	
		STREET 1:		3661 HORSEBLOCK ROAD
		CITY:			MEDFORD
		STATE:			NY
		ZIP:			11763
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-05-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

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            <rptOwnerName>Siebert Lawrence A.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3661 HORSEBLOCK ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MEDFORD</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11763</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <value>Common Stock</value>
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            <transactionTimeliness>
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            <transactionAmounts>
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                <transactionPricePerShare>
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    <ownerSignature>
        <signatureName>Lawrence A. Siebert</signatureName>
        <signatureDate>2008-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----