The 1979 Fianna Fáil leadership election began in December 1979, when Jack Lynch resigned as party leader and Taoiseach. Lynch had been party leader for thirteen years and Taoiseach for over nine years. His successor was elected by the members of the Fianna Fáil parliamentary party on 7 December 1979. After one ballot the election was won by Charles Haughey.

John Mary Lynch was an Irish Fianna Fáil politician who served as Taoiseach from 1966 to 1973 and 1977 to 1979, Leader of Fianna Fáil from 1966 to 1979, Leader of the Opposition from 1973 to 1977, Minister for Finance from 1965 to 1966, Minister for Industry and Commerce from 1959 to 1965, Minister for Education 1957 to 1959, Minister for the Gaeltacht from March 1957 to June 1957, Parliamentary Secretary to the Minister for Lands and Parliamentary Secretary to the Government from 1951 to 1954. He served as a Teachta Dála (TD) from 1948 to 1981.