Valens (Latin: Flavius Julius Valens Augustus; 328 – 9 August 378) is the Eastern Roman Emperor from 364 to 378.

He is given the eastern half of the empire by his brother Valentinian I after the latter's accession to the throne.

Valens, sometimes known as the Last True Roman, is defeated and killed in the Battle of Adrianople, which marks the beginning of the collapse of the decaying Western Roman Empire.