The former Olympique Lyon and Marseille player has signed a three-year deal, the club said in a statement.
Lille have already signed Czech defender David Rozehnal, Nigerian goalkeeper Vincent Enyeama and France midfielder Dimitri Payet during the close-season.
Coach Rudi Garcia, whose side are gearing up for an assault on the Champions League, told L'Equipe newspaper he was desperate to keep highly-rated winger Eden Hazard and said a mooted move to Paris Saint-Germain would be a step down.
Hazard, as well as team-mate Gervinho, have been strongly linked with moves to Arsenal.
Lille President Michel Seydoux recently revealed that no offer for the player has been made, although the Ivorian is keen to joining the Gunners.
"We know that Gervinho is keen on Arsenal,” he told RMC. “For the moment, there has been simple contact, but we have not received a concrete offer yet."
Manchester City and Liverpool - as well as Arsenal and PSG - have been linked with moves for the highly rated Hazard.
But Lille General Manager is confident that their prized asset is staying put.
"Eden's not for sale," he told RMC. "We can't let one of our best players leave.
"He'll be with us next season."
NEWS:Lille seal deals for Rozehnal and EnyeamaNEWS: Payet pens deal with champions Lille
NEWS:Gervinho keen on Arsenal switch
