    <SEC-DOCUMENT>0001047469-19-002750-index.html : 20190430
    <SEC-HEADER>0001047469-19-002750.hdr.sgml : 20190430
    <ACCEPTANCE-DATETIME>20190430160137
    ACCESSION NUMBER:		0001047469-19-002750
    CONFORMED SUBMISSION TYPE:	DEF 14A
    PUBLIC DOCUMENT COUNT:		6
    CONFORMED PERIOD OF REPORT:	20190619
    FILED AS OF DATE:		20190430
    DATE AS OF CHANGE:		20190430
    EFFECTIVENESS DATE:		20190430

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			RHYTHM PHARMACEUTICALS, INC.
    		CENTRAL INDEX KEY:			0001649904
    		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
    		IRS NUMBER:				462159271
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		DEF 14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-38223
    		FILM NUMBER:		19781540

    	BUSINESS ADDRESS:
    		STREET 1:		500 BOYLSTON STREET
    		STREET 2:		11TH FLOOR
    		CITY:			BOSTON
    		STATE:			MA
    		ZIP:			02116
    		BUSINESS PHONE:		857-264-4280

    	MAIL ADDRESS:
    		STREET 1:		500 BOYLSTON STREET
    		STREET 2:		11TH FLOOR
    		CITY:			BOSTON
    		STATE:			MA
    		ZIP:			02116

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	RHYTHM METABOLIC, INC.
    		DATE OF NAME CHANGE:	20150803
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEF 14A
    <SEQUENCE>1
    <FILENAME>a2238576zdef14a.htm
    <DESCRIPTION>DEF 14A
    <TEXT>
    Document 1 - file: a2238576zdef14a.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>g73784.jpg
    <DESCRIPTION>G73784.JPG
    <TEXT>
    Document 2 - file: g73784.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>g27022bci001.gif
    <DESCRIPTION>G27022BCI001.GIF
    <TEXT>
    Document 3 - file: g27022bci001.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
    <FILENAME>g27022bci002.gif
    <DESCRIPTION>G27022BCI002.GIF
    <TEXT>
    Document 4 - file: g27022bci002.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>5
    <FILENAME>g27022bei001.gif
    <DESCRIPTION>G27022BEI001.GIF
    <TEXT>
    Document 5 - file: g27022bei001.gif

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>6
    <FILENAME>g27022bei002.gif
    <DESCRIPTION>G27022BEI002.GIF
    <TEXT>
    Document 6 - file: g27022bei002.gif

    </DOCUMENT>
    </SEC-DOCUMENT>