John Martin Costello (January 15, 1903 – August 28, 1976) was an American lawyer and politician who served five terms as a U.S. Representative from California from 1935 to 1945.

Born in Los Angeles, California, the son of Irish immigrants,[1] Costello attended the public schools.

He served as general counsel and manager of the Washington office of the Los Angeles Chamber of Commerce from 1945 to 1947.

This article incorporates public domain material from the Biographical Directory of the United States Congress

This article about a member of the United States House of Representatives from California is a stub.