Mary Montagu may refer to:
Lady Mary Faith Montagu (1911–1983), daughter of the 9th Earl of Sandwich Lady Mary Wortley Montagu (1689–1762), English writer Mary Montagu Douglas Scott, Duchess of Buccleuch (1900–1993), British duchess Mary Montagu, Duchess of Montagu (1689–1751), formerly Lady Mary Churchill, wife of John Montagu, 2nd Duke of Montagu Mary Montagu, Duchess of Montagu (1711–1775), daughter of the above, wife of George Brudenell, later Montagu, 4th Earl of Cardigan, and later Duchess of Montagu Mary Stuart, Countess of Bute (1718–1794), wife of John Stuart, 3rd Earl Stuart
See also Mary Montagu-Scott (born 1964), British interior designer