St. Mary School officially opened in October 1924 with grades one through six and was staffed by Dominican Sisters. The school expanded with grades seven and eight in the 1930s. The first graduating high school class received diplomas in May 1949.

St. Mary School was originally built at the corner of Ninth Street and Orange Avenue. In 1958, a new high school building was constructed on Bob Hall Road where the present facility is located although the services for high school students ceased in 1970.

St. Mary School has played a significant role in the educational community of Orange, and the Catholic community, in particular.