The Musaeum or Mouseion at Alexandria (Ancient Greek: Μουσεῖον τῆς Ἀλεξανδρείας), which included the famous Library of Alexandria, was an institution founded by Ptolemy I Soter or, perhaps more likely, by his son Ptolemy II Philadelphus.
Museion, Musaeum ili Museion u Aleksandriji (starogrčki: Μουσεῖον τῆς Ἀλεξανδρείας), koji je uključivao slavnu knjižnicu Aleksandrije, bio je ustanova koju je utemeljio Ptolemej I. Soter ili, još vjerojatnije, njegov sin Ptolemej II.