Saint Peter's Cathedral, Belfast, is the Catholic cathedral church for the Diocese of Down and Connor, and is therefore the episcopal seat of the Catholic Bishop of Down and Connor. It is located in the Divis Street area of the Falls Road in Belfast, Northern Ireland, and construction began in the 1860s. There are three choirs: the Cathedral Choir, the Down & Connor Schola Cantorum and the Cathedral Girls’ Choir.

The Diocese of Down and Connor, is a Latin Church ecclesiastical territory or diocese of the Catholic Church in Northern Ireland. It is one of eight suffragan dioceses in the ecclesiastical province of the metropolitan Archdiocese of Armagh. Bishop Alan McGuckian is Bishop.