Thomas O'Connor may refer to:
- Thomas O'Connor (bishop) (1755–1803), bishop of Achonry
- Thomas O'Connor (writer) (1770–1855), Irishman who emigrated to New York where he was a journalist
- Thomas O'Connor (Wisconsin politician) (1815–1901), American politician and farmer
- Thomas O'Connor (rancher) (1819–1887), Texas cattle rancher and landowner originally from County Wexford, Ireland
- T. P. O'Connor (1848–1929), Irish nationalist, journalist, and politician
- Tommy O'Connor (criminal) (1880–1951), escaped Chicago convict
- Thomas Martin O'Connor (1913–1998), City Attorney of San Francisco
- Thomas Burton O'Connor, (1914-1952), American journalist
- Tom O'Connor (Gaelic footballer) (1918–1997), Irish Gaelic footballer
- Thomas H. O'Connor (1923–2012), Boston historian
- Thomas J. O'Connor (1925–1996), mayor of Springfield, Massachusetts
- Thomas C. O'Connor (1927–2001), mayor of Norwalk, Connecticut, 1982–1983
- Tommy O'Connor (died 1987), Irish footballer
- Tom O'Connor (comedian) (1939–2021), English comedian
- Santa Claus (Alaska politician), (born Thomas Patrick O'Connor, 1947), American politician
- Tom O'Connor (American football) (born 1963), American football Punter
- Tom O'Connor (priest), local historian
- Thomas O'Connor (footballer) (born 1999), Irish footballer