Mary Thomas may refer to:
- Joyce Arleen (1931â 2023), American actress sometimes credited as Mary Thomas
- Mary-Anne Thomas (born 1963), Australian politician
- Mary Beatrice Thomas (1873âÂÂ1954), British lecturer in chemistry
- Mary Bentley Thomas (1845âÂÂ1923), American suffragist
- Mary F. Thomas (1816âÂÂ1888), American women's rights leader
- Mary Raine (1877âÂÂ1960), Australian businesswoman and philanthropist, also known as Mary Thomas during her first marriage
- Mary Sternberg Thomas (1866âÂÂ1951), American lawyer in Colorado, U.S.
- Mary Thomas (artist) (born 1944), Aboriginal Australian artist at Warmun Art Centre, Turkey Creek, Western Australia
- Mary Thomas (labor leader) (c. 1848âÂÂ1905), one of the leaders of the 1878 "Fireburn" labor riot on St. Croix, West Indies
- Mary Thomas (poet) (1787âÂÂ1875), South Australian diarist, poet, and early settler
- Mary Thomas (politician) (1944âÂÂ2014), American Pima politician and activist
- Mary Thomas (soprano) (1932âÂÂ1997), Welsh soprano
Fictional characters