The Byzantine–Sassanid War of 572–591 is a war fought between the Sassanid Empire of Persia and the Eastern Roman Empire, termed by modern historians as the Byzantine Empire.

It is triggered by pro-Byzantine revolts in areas of the Caucasus under Persian hegemony, although other events contribute to its outbreak.

The fighting is largely confined to the southern Caucasus and Mesopotamia, although it also extends into eastern Anatolia, Syria, and northern Iran.

It is part of an intense sequence of wars between these two empires, which occupy the majority of the 6th and early 7th centuries.

It is also the last of the many wars between them to follow a pattern in which fighting is largely confined to frontier provinces and neither side achieves any lasting occupation of enemy territory beyond this border zone.

It precedes a much more wide-ranging and dramatic final conflict in the early 7th century.