The Bosnia and Herzegovina international left the Gunners on Wednesday (AEDT), having reached an agreement to terminate his contract.
Kolasinac had fallen out of favour at the Premier League club and returned to Schalke on loan last season.
Thank you and good luck, Sead 👊— Arsenal (@Arsenal) January 18, 2022
The 28-year-old is on the move again, joining Ligue 1 side Marseille on a deal until the end of the next campaign.
From @Arsenal to 𝙈𝙖𝙧𝙨𝙚𝙞𝙡𝙚 💙💫— Olympique de Marseille 🇬🇧 🇺🇸 (@OM_English) January 18, 2022
Let's offer a warm welcome to our newest Olympien by doing what we do best!
𝗚𝗜𝗩𝗘𝗔𝗪𝗔𝗬: follow @OM_English + RT this post for your chance to win a @seadk6 signed shirt 👇👇 pic.twitter.com/D2C6UZOyFE
Kolasinac made 118 appearances for Arsenal following his switch from Schalke in June 2017, but only played for Mikel Arteta's men five times this season.
He becomes Marseille's second signing of the January transfer window following the arrival of striker Cedric Bakambu from Beijing Guoan.