The Magnaura (Medieval Μαγναύρα , possibly from Latin Magna Aula, "Great Hall") was a large building in Constantinople, next to the Great Palace. It is equated by scholars with the building that housed the Senate, and which was located east of the Augustaion, close to the Hagia Sophia and next to the Chalke gate. A large gate, described by Procopius, probably made out of marble led into a peristyle courtyard which led to the Magnaura.

The building, a basilica with three naves, was subsequently used as a throne room and a reception hall for foreign embassies. Emperors held large assemblies in this location, particularly at the atrium area on the western side. For instance, the annual ceremony called the silention or the beginning of Lent, included the entire imperial household and bureaucracy arrayed along the great staircase of the Magnaura. Scholars described it as a material projection of Byzantine imperial power over all subjects of the oikoumene.

In ca. 855, the Caesar Bardas established in the palace a school (ekpaideutērion). However, this was not the University of Constantinople, but rather a Philosophical school, because the University of Constantinople was created during the time of Theodosius II in 425 AD.