Moreau Catholic High School is a college preparatory Roman Catholic secondary school sponsored by the Moreau Province of the Congregation of the Holy Cross. It is located in Hayward, California, within the Roman Catholic Diocese of Oakland under the care of Michael C. Barber, the Bishop of Oakland. It opened in 1965 as an all-boys Catholic High School, temporarily located on the parish grounds of . That same year, construction of the permanent campus began at the current location. That construction was completed in the spring of 1967. At the request of Bishop Floyd Begin, Moreau became a coeducational institution in 1969, with the admission of 177 ninth grade girls. Moreau has twice been named a Blue Ribbon School.