Constantine Sathas (Greek: Κωνσταντίνος Σάθας, Athens, 1842 – Paris, 1914) was a Greek historian and researcher.
Sathas is considered one of the founders of Byzantine and post-Byzantine studies in Greece. He performed archival research in Greece, Constantinople, Venice, and Florence. From 1900 onward he lived in Paris until his death in 1914.
Sathas works include:
Greek language
In French and other languages
He collaborated with J.B. Bury and others for an edition of the History of Michael Psellus (Methuen & Co. London, 1899).