William Turnbull may refer to:
William Turnbull (bishop) (died 1454), Scottish bishop William Turnbull (cricketer) (1879–1959), Scottish cricketer Bill Turnbull (1956–2022), British journalist and presenter Bill Turnbull (actor), Canadian actor active 1995–present William Turnbull (artist) (1922–2012), Scottish artist William Turnbull Jr. (1935–1997), American architect William Turnbull (New Zealand architect) (1868–1941), architect based in Wellington, New Zealand William Turnbull (sailor) (1933–2007), Hong Kong sailor William Barclay Turnbull (1811–1863), Scottish antiquary William D. Turnbull (1922–2011), American paleontologist