Erdem began his career at Zeytinburnuspor where he was then discovered by Galatasaray. At this club he played 349 league games and scored 105 times. With Galatasaray won the UEFA Cup and UEFA Super Cup . Two years later he won the Turkish football team a third place at the 2002 World Cup . After nine years of football at Galatasaray, he decided to go to Real Sociedad in Spain to withdraw. He stayed half a year here and went back to his old nest. In 2005 he quit football. Since August 2006 he has been an assistant coach at Istanbul Buyuksehir Belediyespor .
- 60 caps: 11 times he came to scoring with the Turkish national football team
- Third in the 2002 World Cup