Stefano Okaka scored a bicycle kick goal in the 20th minute for Medipol Basaksehir at Nef Stadium in Istanbul.
Mostafa Mohamed's equalizer came in the 87th minute, giving his team a point with a score of 1-1.
Basaksehir's Leo Duarte was shown two yellow cards in the space of a minute in the last minutes of the match.
Having collected 24 points in 17 matches, Galatasaray extended winless run to six matches in the league.
Basaksehir have 29 points to be in third place.
