The twenty-first federal electoral district of Mexico City (Distrito electoral federal 21 de la Ciudad de México; previously "of the Federal District") is one of the 300 electoral districts into which Mexico is divided for elections to the federal Chamber of Deputies and one of the 22 currently operational districts in Mexico City.^[1]

It elects one deputy to the lower house of Congress for each three-year legislative session by means of the first-past-the-post system. Votes cast in the district also count towards the calculation of proportional representation ("plurinominal") deputies elected from the fourth region.^[2][3]

Under the 2023 districting plan, which is to be used for the 2024, 2027 and 2030 federal elections,^[4] the 21st district covers the borough (alcaldía) of Milpa Alta and the bulk of Xochimilco (the north-western portion of that borough is assigned to the 5th district).^[5][1]

National parties
Current
	PAN
	PRI
	PT
	PVEM
	MC
	Morena
Defunct or local only
	PLM
	PNR
	PRM
	PP
	PPS
	PARM
	PFCRN
	Convergencia
	PANAL
	PSD
	PES
	PRD

Twenty-first federal electoral district of Mexico City

Election	Deputy	Party	Term	Legislature
1961	Óscar Ramírez Mijares[6]		1961–1964	45th Congress
1964	Miguel Cobián Pérez[7]		1964–1967	46th Congress
1967	Óscar Ramírez Mijares[8]		1967–1970	47th Congress
1970	Héctor Ayala Guerrero[9]		1970–1973	48th Congress
1973	Mariano Araiza Zayas[10]		1973–1976	49th Congress
1976	Martha Andrade de Del Rosal[11]		1976–1979	50th Congress
1979	Enrique Gómez Corchado[12]		1979–1982	51st Congress
1982	Everardo Gámiz Fernández[13]		1982–1985	52nd Congress
1985	Ofelia Casillas Ontiveros[14]		1985–1988	53rd Congress
1988	Víctor Sarabía Luna[15]		1988–1991	54th Congress
1991	Everardo Gámiz Fernández[16]		1991–1994	55th Congress
1994	Ofelia Casillas Ontiveros[17]		1994–1997	56th Congress
1997	Pedro Salcedo García[18]		1997–2000	57th Congress
2000	Héctor González Reza[19]		2000–2003	58th Congress
2003	Miguel Ángel Toscano[20]		2003–2006	59th Congress
2006	Alejandro Sánchez Camacho[21]		2006–2009	60th Congress
2009	Avelino Méndez Rangel[22]		2009–2012	61st Congress
2012	Alejandro Sánchez Camacho[23]		2012–2015	62nd Congress
2015	Claudia Villanueva Huerta[24]		2015–2018	63rd Congress
2018	Flor Ivone Morales Miranda [es][25][a] Karen Ivette Audiffred Fernández[26]		2018–2019 2019–2021	64th Congress
2021	Flor Ivone Morales Miranda [es][27]		2021–2024	65th Congress
2024[28]	José Carlos Acosta Ruiz[29]		2024–2027	66th Congress

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