Marian Quinn lived in Ireland for a year as a child before moving with her family to America. She returned to Ireland at the age of 13 to live with relatives. Along with her brother, Aidan Quinn, she trained at the Piven Theater Workshop in Chicago and then moved to New York where she played in Down the Flats at the Irish Arts Center. She playing her first film role in BROKEN HARVEST (1994) and took small parts in low-budget American films, including I Shot Andy Warhol (1996), Alchemy (1995) and Under the Bridge (1996). In 1997 she directed a short film, Come To. Since then she has performed in 2x4 (1997), CLAIRE DOLAN (1998), THIS IS MY FATHER (1998), EVELYN (as Sister Theresa) and in CONEY ISLAND BABY (2002) as Mrs Boyle. Her feature debut as a director was the coming of age drama 32A (2007), which she also wrote. Her other brothers are cinematographer Declan Quinn and director Paul Quinn.