Thousands of women wearing Islamic headscarves and men sporting beards were barred from enrolling at Turkish universities for the fourth year running.
More than 500 students at Ankara University's faculty of art and literature were unable to register. Similar bans were enforced in Istanbul.
The country's higher education authority, Yok, is strictly enforcing a secular dress code law that forbids Islamic dress in public buildings.
Next month, parliament will consider changing the law to transfer many of Yok's powers to individual universities.
According to newspaper reports, Yok has taken control of appointments of academic staff at several universities to try to prevent the employment of staff linked to secret Islamic sects.
Ahmet Selamet, the head of the Islamic human rights group, Mazlum-Der, said: "This new policy is part of the ongoing pressure on the staff of the universities."