<SEC-DOCUMENT>0001209191-21-057461.txt : 20210923
<SEC-HEADER>0001209191-21-057461.hdr.sgml : 20210923
<ACCEPTANCE-DATETIME>20210923171749
ACCESSION NUMBER:		0001209191-21-057461
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210921
FILED AS OF DATE:		20210923
DATE AS OF CHANGE:		20210923

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ciulla Thomas
		CENTRAL INDEX KEY:			0001815426

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37783
		FILM NUMBER:		211273261

	MAIL ADDRESS:	
		STREET 1:		C/O CLEARSIDE BIOMEDICAL, INC.
		STREET 2:		900 NORTH POINT PARKWAY, SUITE 200
		CITY:			ALPHARETTA
		STATE:			GA
		ZIP:			30005

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Clearside Biomedical, Inc.
		CENTRAL INDEX KEY:			0001539029
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				452437375
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		900 NORTH POINT PARKWAY
		STREET 2:		SUITE 200
		CITY:			ALPHARETTA
		STATE:			GA
		ZIP:			30005
		BUSINESS PHONE:		678-270-3631

	MAIL ADDRESS:	
		STREET 1:		900 NORTH POINT PARKWAY
		STREET 2:		SUITE 200
		CITY:			ALPHARETTA
		STATE:			GA
		ZIP:			30005
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-09-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001539029</issuerCik>
        <issuerName>Clearside Biomedical, Inc.</issuerName>
        <issuerTradingSymbol>CLSD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001815426</rptOwnerCik>
            <rptOwnerName>Ciulla Thomas</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CLEARSIDE BIOMEDICAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>900 NORTH POINT PARKWAY, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>ALPHARETTA</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30005</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Medical Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-09-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2560</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.40</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>255560</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 represents shares required to be sold by the Reporting Person to satisfy tax withholding obligations in connection with the settlement of restricted stock units. The sale occurred automatically to satisfy the tax withholding obligations to be funded by a &quot;sell to cover&quot; transaction pursuant to a Rule 10b5-1 trading plan.</footnote>
        <footnote id="F2">Includes 4,998 shares acquired under the Issuer's employee stock purchase plan on June 30, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mark Ballantyne, Attorney-in-Fact</signatureName>
        <signatureDate>2021-09-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
