Yobo, who has spent the last two seasons on loan at the Istanbul-based club, was expected to stay in Turkey after scoring twice in 62 Turkish league matches since falling out of favour at Goodison Park.
The 31-year-old former Marseille centre-half has signed a three-year deal. The fee was undisclosed.
Yobo became the first African player to captain Everton, for whom he played in over 200 Premier League games.
But the signings of Sylvian Distin and John Heitinga forced him out of the first-team, and he was allowed to join the Turkish runners-up initially to get first-team football.