The governing body said Friday that it had banned the defender "for failing to comply with the general principles of conduct, for violating the basic rules of decent conduct, for using sports events for manifestations of a non-sporting nature and for bringing the sport of football into disrepute."
Demiral scored both goals Tuesday in a 2-1 win over Austria to earn Turkey's place in the quarterfinals and celebrated with a hand sign associated with an ultra-nationalist group.
After scoring the second goal he made a sign with each hand that is used by Turkish nationalists and associated with the Turkish ultra-nationalist organization Ulku Ocaklari, which is more widely known as the Gray Wolves.
Demiral will miss Turkey's match with the Netherlands in Berlin on Saturday.