St. Leo may refer to one of several saints named Leo, or:
Places
Australia St Leo's Catholic College, Sydney St Leo's College, University of Queensland, Brisbane
Canada Saint Leo's Elementary School (Brantford), Ontario St. Leo's Roman Catholic Church, Mimico
Ireland St Leo's College, Carlow
United States St. Leo, Florida Saint Leo Abbey St. Leo, Kansas St. Leo, Minnesota Saint Leo, West Virginia
Schools Saint Leo University, St Leo, Florida St. Leo the Great School, Oakland, California St. Leo the Great School, San Jose, California St.Leo's Parish School, Elmwood Park, New Jersey St. Leo Catholic School, Winston-Salem, North Carolina St. Leo Primary School, KwaZulu-Natal Province, South Africa
Churches named St. Leo Saint Leo the Great Parish, within the Roman Catholic Diocese of San Jose, California St.Leo's Roman Catholic Church, Elmwood Park, New Jersey Chapel of St Leo, Żurrieq, Malta
Other St. Leo's (soccer team), an early twentieth century American soccer team