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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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 2+zBPCuxM6cgCNbNOGWtvQ==

<SEC-DOCUMENT>0001293462-08-000013.txt : 20080605
<SEC-HEADER>0001293462-08-000013.hdr.sgml : 20080605
<ACCEPTANCE-DATETIME>20080605152334
ACCESSION NUMBER:		0001293462-08-000013
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080603
FILED AS OF DATE:		20080605
DATE AS OF CHANGE:		20080605

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:		08882887

	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>2008-06-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001291343</rptOwnerCik>
            <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>Chairman &amp; President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to purchase common stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.13</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-06-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.13</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-06-03</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-06-13</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>250000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>250000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <ownerSignature>
        <signatureName>Lawrence A. Siebert</signatureName>
        <signatureDate>2008-06-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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