| William Canniffe | |
| Birth Name: | William Denis Canniffe[1] |
| Birth Date: | 1 April 1885[2] |
| Birth Place: | Queensland, Australia |
| Death Date: | 25 September 1956 (aged 71)[3] |
| Death Place: | Queensland, Australia |
| Ru Position: | lock |
| Repyears1: | 1907 |
| Repteam1: | Wallabies |
| Repcaps1: | 1 |
| Reppoints1: | 0 |
William Denis Canniffe (1 April 1885 – 25 September 1956) was a rugby union player who represented Australia.
Canniffe, a lock, claimed 1 international rugby cap for Australia.