The Diocese of Mercedes () is a Latin Church ecclesiastical territory or diocese of the Catholic church in Uruguay.
The diocese was erected in 1960, from parts of both the Diocese of Salto and the Diocese of San José de Mayo. The diocese is a suffragan of the Archdiocese of Montevideo. Its see is at the Cathedral of Mercedes.
The current bishop is Carlos MarÃÂa Collazzi Irazábal, who was appointed in 1995.