Denis Allen (2 January 1896 – 29 March 1961) was an Irish politician. In 1926 Allen was the Officer Commanding of the North Wexford Battalion of the Irish Republican Army. Allen later became a Fianna Fáil politician. Allen was an unsuccessful candidate at the June 1927 general election, but later that year at the September 1927 general election he was elected to Dáil Éireann as Fianna Fáil Teachta Dála (TD) for the Wexford constituency. He was re-elected at the 1932 general election, but lost his seat at the 1933 general election.