Dudley Ryder, 6th Earl of Harrowby (11 October 1892 – 7 May 1987), known as Viscount Sandon from 1900 to 1956, was a British peer and Conservative Member of Parliament. Harrowby was the son of John Ryder, 5th Earl of Harrowby, and the Hon. Mabel Danvers Smith. William Henry Smith, another former Member of Parliament, was his maternal grandfather. He was educated at Eton College and Christ Church, Oxford, graduating as B.A. He was made an honorary D.Litt. by the university in 1964. He was succeeded in his titles by his eldest son Dudley.