Oliver James Flanagan (22 May 1920 – 26 April 1987) was an Irish Fine Gael politician who served as Minister for Defence from 1976 to 1977 and as a Parliamentary Secretary from 1954 to 1957 and from 1975 to 1976. He served as a Teachta Dála (TD) for the Laois-Offaly constituency from 1943 to 1987. He was Father of the Dáil from 1977 to 1987. He was elected to the Dáil fourteen times between 1943 and 1982, topping the poll on almost every occasion. He was Father of the Dáil from 1977 until his retirement in 1987, and he remains one of the longest-serving members in the history of the Dáil.