Thomas E. Dewey (1902–1971) was Governor of New York.
Thomas Dewey may also refer to:
- Thomas Charles Dewey (1840–1926), President of the Prudential Assurance Company
- Thomas B. Dewey (1915–1981), American crime novelist
- Thomas E. Dewey Jr. (born 1932), son of the governor, investment banker
- Thomas R. Dewey (born 1978), American actor, producer, and writer