Marion Fairfax (October 24, 1875 – October 2, 1970) was an American screenwriter and Broadway playwright.
Born as Marion Neiswanger in Richmond, Virginia, her best known credit was the screenplay for The Lost World (1925). She was married to actor Tully Marshall from 1899 until his death in 1943. She did not remarry.
She died in Los Angeles, California, aged 94.