<SEC-DOCUMENT>0000899243-23-007332.txt : 20230307
<SEC-HEADER>0000899243-23-007332.hdr.sgml : 20230307
<ACCEPTANCE-DATETIME>20230307160523
ACCESSION NUMBER:		0000899243-23-007332
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230303
FILED AS OF DATE:		20230307
DATE AS OF CHANGE:		20230307

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Vounatsos Michel
		CENTRAL INDEX KEY:			0001672709

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38205
		FILM NUMBER:		23712551

	MAIL ADDRESS:	
		STREET 1:		BIOGEN INC.
		STREET 2:		225 BINNEY ST.
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Zai Lab Ltd
		CENTRAL INDEX KEY:			0001704292
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4560 JINKE ROAD
		STREET 2:		BLDG. 1, 4F, PUDONG
		CITY:			SHANGHAI
		STATE:			F4
		ZIP:			201210
		BUSINESS PHONE:		862161632588

	MAIL ADDRESS:	
		STREET 1:		4560 JINKE ROAD
		STREET 2:		BLDG. 1, 4F, PUDONG
		CITY:			SHANGHAI
		STATE:			F4
		ZIP:			201210
</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>2023-03-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001704292</issuerCik>
        <issuerName>Zai Lab Ltd</issuerName>
        <issuerTradingSymbol>ZLAB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001672709</rptOwnerCik>
            <rptOwnerName>Vounatsos Michel</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ZAI LAB LIMITED</rptOwnerStreet1>
            <rptOwnerStreet2>314 MAIN STREET, 4TH FLOOR, SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>American Depositary Shares</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2023-03-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>18332</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18332</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Each American Depositary Share (ADS) represents ten Ordinary Shares of the issuer. Our ADSs and Ordinary Shares are fully fungible. For purposes of this Form 4, we are reporting this in terms of ADSs.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Bruce Blefeld, Attorney-in-Fact</signatureName>
        <signatureDate>2023-03-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
