Mary Foster may refer to:
Mary Foster (biochemist) (1865–1960), American biochemist Mary LeCron Foster (1914–2001), American anthropological linguist Mary Robinson Foster (1844–1930), Hawaiian philanthropist Mary Parke Foster (1840–1922), president general of the Daughters of the American Revolution T. Mary Foster, New Zealand behavioural psychologist and professor Mary Cardona-Foster, American contestant on the American TV series The Amazing Race