FC Lorient Bretagne Sud is a French football club based in Lorient, Brittany.
Lorient were formed as an amateur club on 2 April 1926 and known as Football Club Lorientais. They first played in the regional third division, but progressed to join the Division d'Honneur in 1929.

The club turned professional in 1995, although the club has had two earlier periods as a professional club between 1967-1977 and 1988-1991.

The club won the French Cup in 2002 and were finalists in the Coupe de la Ligue the same year. In the 2005-06 season, the club finished third in Ligue 2, earning promotion to Ligue 1.