1989–90 Galatasaray S.K. (men's basketball) season

Galatasaray SK Men's 1989–1990 season is the 1989–1990 basketball season for Turkish professional basketball club Galatasaray SK.

The club competes in:
 * Turkish Basketball League

Squad changes for the 1989–1990 season
In:

Out:

Regular season
Pts=Points, Pld=Matches played, W=Matches won, L=Matches lost, F=Points for, A=Points against

Quarter-finals Group
Fenerbahçe and Galatasaray joined semi-finals automatically. Tofaş SAS, the second league winner, joined play off quarter finals. Efes Pilsen and Paşabahçe SK qualified for the semi-finals after the matches in Ankara.