The Ligue 1 club made the announcement on Thursday on their website and social media pages that the veteran striker has returned to France.
Lacazette 31, first gained the limelight at Lyon in 2010 where he scored 129 goals then went on to be one of Europe's most sought after strikers. His time at Lyon was brought to an end in 2017 when he left for Arsenal.
Speaking to Arsenal's official website before his exit, the striker - who won the FA Cup with the Gunners in 2020 - said: "I want to keep all the good moments I had in the club because for me it was just a pleasure to play for a club that, since I was young, I dreamt of. I'm really happy to have played for five years for Arsenal.
Once a gunner, Always a Gunner.❤️♣️ pic.twitter.com/RouDBIiGVy— Alexandre Lacazette (@LacazetteAlex) June 3, 2022
"There's a board at the stadium with all the winners' names on it, and in my first season, I told my dad that one day I would be on it. So I'm really proud I made it."
Arsenal boss Mikel Arteta added: "Laca has been a fantastic player for us. He's been a real leader on and off the pitch and has been a very important influence to our younger players.
"His commitment with us has been exceptional and we wish him and his family success and happiness."