Saint Xavier High School ( ), or simply St. X, is a private, all-boys high school near Cincinnati, Ohio, United States. The school is one of four all-boys Catholic high schools in the Archdiocese of Cincinnati, but it is run by the Society of Jesus (Jesuits) instead of the archdiocese. St. Xavier has 1,535 students, making it the largest private high school in Ohio and one of the 100 largest high schools in that state.