William Foster
William Foster is the name of:
- William Foster ( historian ) ( 1863-1951 ), British historian
- William Foster ( swimmer ), British swimmer
- William Harnden Foster (1886-1941), American painter, writer, filmmaker and journalist
- William P. Foster (1919-2010), American musician, band leader and music teacher
- William Wasbrough Foster (1875-1954), British- Canadian climber, politicians, military and police officer
- William Z. Foster (1881-1961), American politician
- Disambiguation