John Charles Depler (January 6, 1899 – December 5, 1970) was a professional football player and coach. Prior to his professional career, he played college football for the Illinois Fighting Illini football team of the University of Illinois. There he helped lead Illinois to its second national championship in 1919, and earned first-team All-American honors in 1920. After graduation, Depler played for the Hammond Pros of the National Football League (NFL). The following year, he was hired as an assistant coach to Frank "Buck" O'Neill, at Columbia University, where he stayed for the next eight seasons.