The 2009–10 season was French football club Olympique Lyonnais's 51st season in Ligue 1 and was their 21st consecutive season in the top division of French football. For the first time in seven years, Lyon entered the football season without defending the Ligue 1 title. They were overthrown by Bordeaux who claimed the title on the final day of 2008–09 season. This was also the first time in nine years Lyon had to earn qualification to the group stage of the UEFA Champions League as they began from the playoff round, due to their third-place finish last season.
On 6 June 2009, it was announced by Lyon that fitness coach Robert Duverne had quit his position to focus full-time on the French national team, who were attempting to qualify for the 2010 World Cup. Vincent Espié, who had previously worked as fitness coach for Claude Puel's former club Lille, was brought in as his replacement.
Departures this summer include long time Lyonnais Juninho, who, after spending a respectable eight seasons at the club, moved to Qatari club Al-Gharafa.Defender Sandy Paillot joined fellow Ligue 1 club Grenoble for a fee of €2 million after spending almost a year-and-a-half on loan at the club. Also during this summer window, a host of youth players who were either deemed surplus to requirements or looking to find some significant playing time departed the club. Pierrick Valdivia, Ayan Si-Mohamed and Alexis Carra moved to Sedan, Stade Reims and Italian club Vicenza, respectively. Midfielder Romain Dedola and defender Morgan Ancian both joined Strasbourg, while Quentin Barlet and Jérémy Dequelson joined lesser rivals Lyon Duchère. Another youth player, Jérémy Pied, joined Metz on loan for the entire 2009–10 season with hopes that the player will receive greater playing time.