Donald Ogden Stewart (November 30, 1894 – August 2, 1980) was an American writer and screenwriter best known for his sophisticated golden age comedies and melodramas such as The Philadelphia Story (based on the play by Philip Barry), Tarnished Lady and Love Affair.

Stewart worked with a number of the directors of his time, including George Cukor (a frequent collaborator), Michael Curtiz and Ernst Lubitsch.

He graduated from Yale University, where he became a brother to the Delta Kappa Epsilon fraternity (Phi chapter), in 1916 and served in the naval reserves in World War I.

He was friends with Dorothy Parker, Robert Benchley, George S. Kaufman, and Ernest Hemingway, who partly based the character of Bill Gorton in The Sun Also Rises on Stewart.

During the Second Red Scare Stewart was blacklisted in 1950 and the following year he and his wife, activist and writer Ella Winter (they had married in 1939), emigrated to England.