William Ker may refer to:
William Ker, Lord Ker (d. 1618), the eldest son of Robert Ker, 1st Earl of Roxburghe William Ker, 2nd Earl of Roxburghe (d. 1675), Scottish nobleman William Paton Ker (1855–1923), Scottish literary scholar and essayist William Ker (footballer) (1852–1911), Scottish international footballer William Balfour Ker (1877–1918), American illustrator
See also William Kerr (disambiguation)