Saint Mary's High School (SMHS), founded in 1876, is a Roman Catholic, co-educational, college preparatory school in Stockton, California, USA. The school is under the jurisdiction of the Diocese of Stockton and sponsored by the Salesian order of the Oblates of St. Francis de Sales priests and brothers (Toledo-Ohio Province). St. Mary's has long established itself as the premier private secondary school in the San Joaquin County.