Grey sisters may refer to:
Graeae or Grey sisters, three old women from Greek mythology Lady Jane Grey, Lady Katherine Grey, and Lady Mary Grey from 16th-century Tudor England Meredith Grey, Lexie Grey and Molly Grey-Thompson from the TV series Grey's Anatomy
Catholic religious sisters Daughters of Charity of Saint Vincent de Paul or Grey sisters, society of apostolic life based in France Grey Nuns, Canadian religious institute based in Montreal Grey Sisters of the Immaculate Conception based in Pembroke, Ontario, Canada Family Care Sisters or Grey sisters, Australian congregation founded by Cecily Maude O'Connell
See also The Grey Sisterhood, 1916 American silent film Grey Sister, 2018 novel by Mark Lawrence