<SEC-DOCUMENT>0001628280-19-001282.txt : 20190213
<SEC-HEADER>0001628280-19-001282.hdr.sgml : 20190213
<ACCEPTANCE-DATETIME>20190213120543
ACCESSION NUMBER:		0001628280-19-001282
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190212
FILED AS OF DATE:		20190213
DATE AS OF CHANGE:		20190213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TCHELET RONEN
		CENTRAL INDEX KEY:			0001761230

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-55264
		FILM NUMBER:		19595182

	MAIL ADDRESS:	
		STREET 1:		140 INTRACOASTAL POINTE DRIVE
		STREET 2:		SUITE 404
		CITY:			JUPITER
		STATE:			X1
		ZIP:			33477

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DYADIC INTERNATIONAL INC
		CENTRAL INDEX KEY:			0001213809
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL ORGANIC CHEMICALS [2860]
		IRS NUMBER:				450486747
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		140 INTRACOASTAL POINTE DRIVE
		STREET 2:		SUITE 404
		CITY:			JUPITER
		STATE:			FL
		ZIP:			33477
		BUSINESS PHONE:		561-743-8333

	MAIL ADDRESS:	
		STREET 1:		140 INTRACOASTAL POINTE DRIVE
		STREET 2:		SUITE 404
		CITY:			JUPITER
		STATE:			FL
		ZIP:			33477

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CCP WORLDWIDE INC
		DATE OF NAME CHANGE:	20030110
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>wf-form3_155007752777326.xml
<DESCRIPTION>FORM 3
<TEXT>
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    <periodOfReport>2019-02-12</periodOfReport>

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        <issuerTradingSymbol>DYAI</issuerTradingSymbol>
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            <rptOwnerZipCode>33477-5094</rptOwnerZipCode>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>VP of Research and Bus. Dvlpmt</officerTitle>
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                    <value>50000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ronen Tchelet</signatureName>
        <signatureDate>2019-02-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
