Mary of the United Kingdom may refer to:
* Mary of Teck (1867–1953), queen consort, queen dowager and queen mother of the United Kingdom Princess Mary, Duchess of Gloucester and Edinburgh (1776–1857), fourth daughter of King George III Mary, Princess Royal and Countess of Harewood (1897–1965), only daughter of King George V
See also Mary of England (disambiguation) Princess Mary (disambiguation) Queen Mary (disambiguation)