St. Pius X Preparatory Seminary was the minor seminary of the Diocese of Rockville Centre. It was founded in 1961 and closed in 1984. It was originally headquartered in Hempstead, New York, but moved to its permanent home on Front Street in Uniondale, New York in the early 1960s. At that time, it served as both a high school seminary and a two-year junior college. After the establishment of Cathedral College, Douglaston, the junior college portion closed. St. Pius X's high school was closed in 1984 after a bitter battle for preservation between students, parents, alumni, and friends on the one side, and the diocese, led by Bishop John McGann, on the other.