Gökmedrese or Gök Medrese (literally: "Celestial Madrasah" or "Blue Madrasah"; Persian: گوک مدرسه), also known as Sahibiye Medresesi, is a 13th-century medrese, an Islamic educational institution, in the city of Sivas, Turkey.

The medrese was commissioned by Sahip Ata Fahrettin Ali, a vizier and the de facto ruler of Seljuk Sultanate of Rûm after the death of Pervane in 1277.

The medrese was constructed by an architect[a] known as "Kaloyan" (Byzantine Greek: Καλό Γιάννη, "Kalo Yianni," literally 'good John') from Konya.

[2] In middle age Islamic countries Vakıf was a source of revenue, endowed for the exploitation and the maintenance of the foundations as well as for the salaries of the staff.

^ a: possibly of Armenian[3][4][5] or Cappadocian Greek origin[6] La signature Kaloyan du Gok Medrese de Sivâs (1270) est également arménienne