The Diocese of Rome, also called the Vicariate of Rome, is a Latin diocese of the Catholic Church under the direct jurisdiction of the Pope, who is Bishop of Rome and hence the supreme pontiff and head of the worldwide Catholic Church. As the Holy See, the papacy is a sovereign entity with diplomatic relations, and civil jurisdiction over the Vatican City State located geographically within Rome. The Diocese of Rome is the metropolitan diocese of the province of Rome, an ecclesiastical province in Italy. According to Catholic tradition, the first bishop of Rome was Saint Peter in the first century. The incumbent since 13 March 2013 is Pope Francis.

In church governance, a diocese or bishopric is the ecclesiastical district under the jurisdiction of a bishop.