The 2011–12 season of Olympique Lyonnais was the club's 53rd season in Ligue 1. After a third-place finish last season, the club played in the UEFA Champions League for the 12th consecutive season.

At the end of the 2010–11 season, fans had become dissatisfied with then manager Claude Puel, despite the club managing to finish in third place, synonymous with qualification to the UEFA Champions League Play-off round. However, due to poor results and a falling out with the club's hierarchy, he was sacked. He was replaced by former technical coach Rémi Garde, who announced his intentions to compete for the league title.

On 17 June, Lyon announced the departure of midfielder Jérémy Toulalan to Málaga for €10 million.

During pre-season training, Yoann Gourcuff suffered another injury blow, this time to his left ankle, which required an operation keeping him out for at least a month.

On 16 July, Brazilian midfielder Ederson was injured to the right knee during a pre-season match against Racing Genk after a collision with teammate Dejan Lovren.

On 12 August Lyon announce the signing of Burkina Faso international defender Bakary Koné from Guingamp for €2 million.

On 27 August, during a match against Montpellier, forward Lisandro López injured his ankle. It was originally feared that he had broken his ankle, as the striker believed he had heard a crack, but scans later alayed these fears. Nevertheless, the Argentine will be out for several weeks.

On 30 August Lyon signed defender Mouhamadou Dabo from Sevilla for a modest €1 million that could rise to €1.8 million if certain playing criteria are met.

...
Wikipedia