William Roy
William Roy is the name of the following people:
- William Roy (reformer) († 1528/1531), English reformer and martyr
- William Roy (General) (1726–1790), Scottish military man and naturalist
- William Roy (actor) (1928–2003), American child actor (as Billy Roy ), composer, musical arranger, and pianist
- William B. Roy (* 1958), American marksman
- William R. Roy (1926–2014), American politician