<SEC-DOCUMENT>0001127430-16-000169.txt : 20161216
<SEC-HEADER>0001127430-16-000169.hdr.sgml : 20161216
<ACCEPTANCE-DATETIME>20161216164122
ACCESSION NUMBER:		0001127430-16-000169
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161214
FILED AS OF DATE:		20161216
DATE AS OF CHANGE:		20161216

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INSMED Inc
		CENTRAL INDEX KEY:			0001104506
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				541972729
		STATE OF INCORPORATION:			VA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		10 FINDERNE AVENUE
		STREET 2:		BUILDING 10
		CITY:			BRIDGEWATER
		STATE:			NJ
		ZIP:			08807
		BUSINESS PHONE:		908-977-9900

	MAIL ADDRESS:	
		STREET 1:		10 FINDERNE AVENUE
		STREET 2:		BUILDING 10
		CITY:			BRIDGEWATER
		STATE:			NJ
		ZIP:			08807

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSMED INC
		DATE OF NAME CHANGE:	20000128

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Pellizzari Christine A
		CENTRAL INDEX KEY:			0001127430

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30739
		FILM NUMBER:		162056768

	MAIL ADDRESS:	
		STREET 1:		10 FINDERNE AVENUE
		CITY:			BRIDGEWATER
		STATE:			NJ
		ZIP:			08807

	FORMER NAME:	
		FORMER CONFORMED NAME:	PELLIZZARI CHRISTINE A
		DATE OF NAME CHANGE:	20001030
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-12-14</periodOfReport>

    <issuer>
        <issuerCik>0001104506</issuerCik>
        <issuerName>INSMED Inc</issuerName>
        <issuerTradingSymbol>INSM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001127430</rptOwnerCik>
            <rptOwnerName>Pellizzari Christine A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10 FINDERNE AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>BUILDING 10</rptOwnerStreet2>
            <rptOwnerCity>BRIDGEWATER</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08807</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>General Counsel &amp; Corp. Sec.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-12-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.72</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.89</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The price in column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $12.61 to $12.82, inclusive.</footnote>
        <footnote id="F2">The price in column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $12.74 to $13.00, inclusive.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Christine Pellizzari</signatureName>
        <signatureDate>2016-12-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
