The Great Mosque or Mosque of Al-Qasr is one of the main and most famous islamic monuments of Tunisia and altought there is no date concerning its foundation , it seems that it was immediately built after the Arabs conquest of the city of Tozeur at the end of seventh century of our era. This monument draws its reputaton from its educational role and its architectural importance. Indeed it played during its history a large scientific role because it took a large number of local renowned scholars such as Abou Zakaria Chokratsi , Abdallah Abou Al-Fadl al-Nahwi and Ibn Chabbat.