Mary Clare (1892–1970) was an English actress of stage, film, and television. Mary Clare may also refer to:
- Mary Clare Brassington (1874–1966), American suffragist
- Mary Clare de Graffenried (1849–1921), American labor researcher and writer
- Mary Clare Kennedy (fl. 1647), Irish nun
- Mary Clare Millea, American former superior general of the Apostles of the Sacred Heart of Jesus
- Mary Clare Moore (1814–1874), Irish Sister of Mercy, Crimean War nurse, and teacher
- Mary Clare Therese Champagne (?–1958), American victim of the Our Lady of the Angels School fire