With two games left, Turkey's most successful club lead the standings with 72 points, three ahead of Basaksehir and six clear of arch-rivals Fenerbahce.
Galatasaray opened the scoring in the first minute after Garry Rodrigues won the ball in the midfield and passed the ball for Younes Belhanda to score.
French striker Bafetimbi Gomis netted the second after 12 minutes, his 28th league goal of the season.
(Writing by Ece Toksabay, editing by Ed Osmond)
