Santa Margarita Catholic High School (abbreviated as SMCHS) is a coeducational college preparatory Roman Catholic high school located in Rancho Santa Margarita, California, United States. SMCHS is owned and operated by the Diocese of Orange, and was opened in 1987 under the direction of the Bishop of Orange. Although it follows the Catholic tradition, admission is open to students of all faiths. As of the spring 2016, 1,752 students were enrolled in grades 9 through 12.