ФИБА Европа
Geyik was a regular member of the junior national teams of Turkey. With Turkey's junior national teams, he played at the 2009 FIBA Europe Under-16 Championship, the 2010 FIBA Europe Under-18 Championship, the 2011 FIBA Europe Under-18 Championship, the 2012 FIBA Europe Under-20 Championship, and the 2013 FIBA Europe Under-20 Championship. He won the bronze medal at the 2011 FIBA Europe Under-18 Championship.