John Herbert Dudley Ryder, 5th Earl of Harrowby (22 August 1864 – 30 March 1956), briefly known as Viscount Sandon from March to December 1900, was a British peer and Conservative Member of Parliament. Harrowby was the son of Henry Dudley Ryder, 4th Earl of Harrowby, and Susan Juliana Maria Hamilton Dent.