The Roman Catholic Diocese of Pasig is the diocese of the Roman Catholic Church in the Philippines that comprises Pasig City, Pateros, and Taguig City. It was established by Pope John Paul II on June 26, 2003 by virtue of the Papal Bull Deus Caritas. It was formally inaugurated on August 21, 2003, with the installation of Most Reverend Francisco C. San Diego, DD. as its first bishop. The Immaculate Conception Parish, located in the central vicinity of Pasig, was made the cathedral or the seat of the diocese.