Leonard Treash (January 1, 1909 in Pennsylvania – January 31, 1996 in Rochester, New York) was an American bass, opera director, and educator. As a performer he sang leading opera roles throughout the United States under such conductors as Fritz Reiner, Leopold Stokowski, Artur Rodzinski, and Erich Leinsdorf. He was particularly active as a performer with opera companies in Philadelphia, and is especially remembered as the long time director of the opera program at the Eastman School of Music, a post he held for nearly 30 years. He also served as General Director of Chautauqua Opera for 10 seasons and was the first President of the from 1955-1956.