William Tyrrell may refer to:
- William Tyrrell (bishop) (1807–1879), first Anglican Bishop of Newcastle, New South Wales
- William Tyrrell, 1st Baron Tyrrell (1866–1947), British diplomat
- William Tyrrell (RAF officer) (1885–1968), Irish rugby international, military officer, and surgeon to George VI
- George William Tyrrell, Union Army officer
- Disappearance of William Tyrrell, a missing boy from Australia
- William Casper Tyrrell, "Captain W.C." Tyrrell, Texas business magnate