The Marriage of William Ashe is a novel by Mary Augusta Ward that was the best-selling novel in the United States in 1905. It originally appeared in serial form in Harper's Magazine from June 1904 through May 1905, and was published in book form in March 1905. Illustrations were provided by Albert Sterner.

Mary Augusta Ward was a British novelist who wrote under her married name as Mrs Humphry Ward. She worked to improve education for the poor setting up a Settlement in London and in 1908 she became the founding President of the Women's National Anti-Suffrage League.