Sasanian Armenia refer to the periods in which Armenia was under the suzerainty of the Sasanian Empire or specifically to the parts of Armenia under its control such as after the partition of 387 when parts of western Armenia were incorporated into the Roman Empire while the rest of Armenia came under Sasanian suzerainty but maintained its existing kingdom until 428.

In 428 marked the start of a new era known as the Marzpanate period, a period when marzbans, nominated by the Sasanian emperor, governed eastern Armenia, as opposed to the western Byzantine Armenia which was ruled by several princes, and later governors, under Byzantine suzerainty. The Marzpanate period ended with the Arab conquest of Armenia in the 7th century, when the Principality of Armenia was established. An estimated three million Armenians were under the influence of the Sasanian marzpans during this period.

The marzban was invested with supreme power, even imposing death sentences; but he could not interfere with the age-long privileges of the Armenian nakharars. The country as a whole enjoyed considerable autonomy. The office of Hazarapet, corresponding to that of Minister of the Interior, public works and finance, was mostly entrusted to an Armenian, while the post of Sparapet (commander-in-chief) was only entrusted to an Armenian. Each nakharar had his own army, according to the extent of his domain. The "National Cavalry" or "Royal force" was under the Commander-in-chief.