Leo Florian Hauck (November 4, 1888 – January 21, 1950) was an American boxer. During his career he was able to achieve victories over many Hall of Famers including Jack Britton, Jack Dillon, Battling Levinsky, Frank Klaus, Billy Papke, Jeff Smith and Harry Lewis. He also faced the likes of Harry Greb, Gene Tunney and Mike Gibbons. He was inducted into the Ring Magazine hall of fame in 1969, the Pennsylvania Sports Hall of Fame in 1972, and enshrined within the International Boxing Hall of Fame as a part of the 2012 class.