William Leonard
William or Bill Leonard may refer to:
Government
- William Leonard , MP for Dover
- William Leonard , MP for Glasgow St. Rollox, 1931–1950
- J. William Leonard, director of the Information Security Oversight Office
- Bill Leonard , American politician in California
- Billy Leonard, Irish republican politician
Military
- William Leonard, Medal of Honor recipient during the Plains Indian Wars
- William E. Leonard, Medal of Honor recipient in the American Civil War
- William F. Leonard, recipient of the Medal of Honor
- William N. Leonard, American World War II flying ace and United States Navy admiral
Others
- William Andrew Leonard, American author and prelate of the Episcopal Church
- William Ellery Leonard, American poet
- William J. Leonard, American football player
- Bill Leonard , American miler, 1948 1500 m All-American for the Notre Dame Fighting Irish track and field team
- William Robert Leonard or Bobby Leonard, American basketball player and coach
- Bill Leonard , American broadcast journalist
- Bill J. Leonard, American historian of religion