Mary Grey

Mary Grey may refer to:
 * Mary Grey (theologian) (born 1941), English Roman Catholic ecofeminist liberation theologian
 * Lady Mary Grey (1545–1578), sister of Jane Grey, Queen of England
 * Mary Grey, Countess Grey (1776–1861), wife of Charles Grey, 2nd Earl Grey
 * Mary Grey, Countess of Kent (died 1702), English peeress
 * Mary Grey, Baroness Grey de Wilton

Fictional characters

 * Mary Grey, in the 1939 US comedy film 5th Ave Girl, played by Ginger Rogers