Loukas Notaras (Greek: Λουκᾶς Νοταρᾶς; 5 April 1402 – 3 June 1453) was a Byzantine Greek statesman who served as the last megas doux or grand Duke (commander-in-chief of the Byzantine navy) and the last mesazon (chief minister) of the Byzantine Empire, under emperors John VIII Palaiologos and Constantine XI Palaiologos.