Constantine Palaiologos or Palaeologus () may refer to: Constantine Palaiologos (half-brother of Michael VIII) (d.1271), half-brother of Michael VIII Palaiologos and grandfather of Theodora Smilets of Bulgaria Constantine Palaiologos (son of Michael VIII) (1261–1306), son of Michael VIII Palaiologos Constantine Palaiologos (son of Andronikos II) (fl. 1292–1320s), despotes, son of Andronikos II Palaiologos Constantine XI Palaiologos (1405–1453), last ruler of the Byzantine Empire in 1449–1453 Constantine Palaiologos (Papal Guard) (d. 1508), commander of the Papal Guard, possibly son of Andreas Palaiologos