The 1966 Fianna Fáil leadership election in the Republic of Ireland began in October 1966 following the decision of Seán Lemass to resign as party leader and Taoiseach. Lemass had occupied both posts for over seven years and, while there was no pressure on him to resign, he felt that the time was right to hand over to a new generation. His successor was elected by the members of the Fianna Fáil parliamentary party on 9 November 1966. After one ballot the election was won by Jack Lynch.