The Open Sud de France is a men's tennis tournament, part of the ATP Tour. It was voted by tennis players as the best category tournament in 1999.

It was played at the Palais des Sports de Gerland in Lyon from 1987 to 2009 and from 2010 is played at the Montpellier Arena in Montpellier again on indoor hard courts.

Founded in 1987, it was held annually in October at the Palais des Sports de Gerland in Lyon until 2009, before being relocated to Montpellier in 2010. The tournament takes place at the Montpellier Arena, holding 7,500 spectators.

The tournament is one of four French events of the ATP Tour 250 series, along with the Open 13, the Moselle Open, and the Lyon Open. There was no event in 2011 as the tournament moved to a January slot in 2012.