Mary Hardy may refer to:
Mary Hardy (actuary), professor of actuarial science Mary Hardy (diarist) (1733–1809), English brewer's wife and diarist Mary Anne Hardy (c.1825–1891), English novelist and travel writer María Cordero Hardy (born 1932), Puerto Rican scientist whose research has helped in the understanding of the properties of vitamin E Mary Hardy (comedian) (1931–1985), Australian comedian
See also Mary Hardy Reeser (1884–1951), suspected victim of spontaneous human combustion Marieke Hardy (born 1976), Australian writer, broadcaster, television producer and actress