William Leach
William Leach may refer to:
- William Elford Leach, English zoologist and marine biologist
- William Leach , British Labour Party politician, minister in the first Labour government
- William Turnbull Leach, Canadian clergyman and academic
- William Leach , American sprint canoer
- William Leach , English cricketer
- William Leach , English cricketer
- William Leach
- William Leach, American historian