The Cathedral of Saint Mary of the Assumption, also known locally as Saint Mary's Cathedral, is the principal church of the Archdiocese of San Francisco in San Francisco, California. It is the mother church of the Catholic faithful in the California counties of Marin, San Francisco and San Mateo and is the metropolitan cathedral for the Ecclesiastical province of San Francisco.
The cathedral is located in the Cathedral Hill neighbourhood of San Francisco. The present cathedral replaced one (1891–1962) of the same name. The original Cathedral of Saint Mary of the Immaculate Conception was built in 1853–54 at California Street and Grant Avenue and still stands today. It is now known as Old Saint Mary's Cathedral.