Michail Asen (Bulgarian: Михаил Асен) (c. 1322–1355) was the eldest son of Ivan Alexander of Bulgaria from his marriage with Theodora of Wallachia. After his father acceded to the throne in 1331, the young prince was proclaimed co-Emperor. He was to succeed his father under the name Michael IV Asen. The heir to the throne was the pride of the royal family and was said to possess "all virtues". He married Maria, renamed Irina, the daughter of Andronikos III Palaiologos.