The Diocese of San Miguel () is a Latin Church ecclesiastical territory or diocese of the Catholic Church in El Salvador. It is a suffragan diocese in the ecclesiastical province of the metropolitan Archdiocese of San Salvador. The Diocese of San Miguel was erected on 11 February 1913.
Bishops
Ordinaries
Juan Antonio Dueñas y Argumedo (1913–1941) Miguel Angel Machado y Escobar (1942–1968) Lorenzo Michele Joseph Graziano, O.F.M. (1968–1969) José Eduardo Alvarez Ramírez, C.M. (1969–1997) Romeo Tovar Astorga, O.F.M. (1997–1999), appointed Bishop of Santa Ana Miguel Angel Morán Aquino (2000–2016), appointed Bishop of Santa Ana Fabio Reynaldo Colindres Abarca (2017–present)
Coadjutor bishops
Lorenzo Michele Joseph Graziano, O.F.M. (1965–1968) Romeo Tovar Astorga, O.F.M. (1996–1997)
Other priest of this diocese who became bishop
Gregorio Rosa Chávez, appointed Auxiliary Bishop of San Salvador in 1982, cardinal in 2017