Thomas Barker may refer to:

• Thomas Barker (academic), principal of Brasenose College, Oxford, 1777–1785
• Thomas Barker (Australian politician) (1799–1875), Australian politician in New South Wales
• Thomas Barker (cricketer, born 1798) (1798–1877), English cricketer
• Thomas Barker (cricketer, born 1812) (1812–1873), English cricketer
• Thomas Barker (fishing guide) (fl. 1591–1651), British author who wrote about fishing
• Thomas Barker (mathematician) (1838–1907), Scottish mathematician and professor of pure mathematics
• Thomas Barker (meteorologist) (1722–1809), weather observer
• Thomas Barker (painter) (1769–1847), British painter of landscape and rural life
• Thomas F. Barker (1828–1896), political figure in New Brunswick
• Thomas Henry Barker (1841–1917), secretary of the Liverpool Chamber of Commerce
• Thomas Holliday Barker (1818–1889), English temperance advocate and vegetarian
• Thomas Jones Barker (1815–1882), English historical and portrait painter
• Thomas Richard Barker (1799–1870), English Independent minister and college tutor
• Thomas William Barker (1861–1912), Carmarthenshire solicitor
• Tom Barker (basketball) (born 1955), retired American basketball player
• Tom Barker (designer) (born 1966), British designer and academic
• Tom Barker (trade unionist) (1887–1970), New Zealand tram conductor, trade unionist and socialist
• Tom Barker (rugby union) (born 1956), Australian rugby union player