Thomas Harrison may refer to:
- Thomas Harrison (architect) (1744–1829), English architect and bridge engineer
- Thomas Harrison (cyclist) (born 1942), Australian cyclist
- Thomas Harrison (footballer) (1867–1942), English footballer for Aston Villa
- Thomas Harrison (general) (1823–1891), Confederate States Army brigadier general, district judge
- Thomas Harrison (minister) (1619–1682), English nonconformist minister, active in Virginia and Ireland
- Thomas Harrison (ship-owner) (1815–1888), Liverpool ship-owner
- Thomas Harrison (soldier) (1606–1660), sided with Parliament in the English Civil War
- Thomas Harrison (translator) (1555–1631), English Puritan scholar and a translator for the King James Version of the Bible
- Thomas Harrison (surveyor), surveyor in Jamaica
- T. Alexander Harrison (1853–1930), American artist
- Thomas Elliot Harrison (1808–1888), civil engineer
- Thomas Sinclair Harrison (1898–?), South African World War I flying ace
- Thomas W. Harrison (1856–1935), U.S. Representative from Virginia (second name Walter; had a cousin Thomas Willoughby Harrison (1824–1910) West Virginia judge
- Tom Harrison (baseball) (1945–2023), baseball pitcher
- Tom Harrison (cricketer) (born 1971), English cricketer
- Tom Harrison (musician) (born 1985), British jazz musician
- Tom Harrison (politician) (1864–1944), Australian politician
- Tommy Harrison (1892–1931), English boxer of the 1900s-1920s
- Tommy Harrison (footballer) (born 1974), Scottish footballer for Heart of Midlothian