Maria Adelaide

Maria Adelaide can refer to:
 * Marie Adélaïde of Savoy (1685–1712), wife of Louis, Dauphin of France, Duke of Burgundy
 * Adelaide of Austria (1822–1855), queen consort of Sardinia
 * Infanta Maria Antonia of Portugal (Maria Antonia Adelaide, 1862–1959), daughter of king of Portugal
 * Infanta Maria Adelaide of Portugal (1912–2012), daughter of claimant to Portuguese throne
 * Maria Adelaide Aboim Inglez (1932–2008), Portuguese communist and opponent of the Estado Novo regime
 * Maria Adelaide Amaral (born 1942), Portuguese Brazilian playwright, screenwriter and novelist
 * Maria Adelaide Lima Cruz (1908–1985), Portuguese painter and theatrical designer
 * Maria Adelaide Sneider (1937–1989), Italian mathematician