William Warner
William or Bill Warner may refer to:
- William Warner (poet), English poet
- William H. Warner, officer in the U.S. Army's Corps of Topographical Engineers
- William Smith Warner, American politician
- William Warner (Missouri politician), American politician
- William Warner (cricketer), English cricketer
- William John Warner or Cheiro, Irish astrologer and palmist
- William Warner (Conservative politician), British Army officer and politician
- Bill Warner (American football), American football player and coach
- W. Lloyd Warner, American anthropologist
- William W. Warner, American author, winner of a Pulitzer Prize in 1977
- Bill Warner (motorcyclist), American motorcycle racer
- William Warner (Michigan politician, born 1806), American politician
- William Warner (Michigan politician, born 1812), American politician