Euphratensis (Latin for "Euphratean"; Ancient Greek: Εὑφρατησία, Euphratēsía), fully Augusta Euphratensis, was a late Roman and then Byzantine province in Syrian region, part of the Byzantine Diocese of the East.

Sometime between 330 and 350 AD (likely c. 341), the Roman province of Euphratensis was created out of the territory of Coele Syria along the western bank of the Euphrates.

Its capital was Cyrrus[2] or perhaps Hierapolis Bambyce.

The Roman Catholic and Orthodox saints Sergius and Bacchus were supposedly martyred in the city of Resafa in Euphratensis, and the city was later renamed Sergiopolis.

Other cities in the province were Samosata and Zeugma.