His father Dimitrie had held high office in the Moldavian court where he was "Mare Postelnic" ("Grand Chamberlain") from 1599 to 1606.

Barnovschi assumes high office with the princes of Moldavia: he is "Spătar" ("Constable") from 1615 to 1618, "Pârcălab" ("Châtelain") of Hotin from 1618 to 1622 and "Hetman" ("Military Governor" ") from Suceava from 1622 to 1626.

At the end of his reign, his father-in-law Radu Mihnea, weakened by the disease, gives him an important role in the management of the country.

On the secular level, however, Miron Barnovschi Movilă left a bad memory in the Moldavian peasantry, because it is he who introduced serfdom by his decree of January 16, 1628, which fixes the peasants to the land of their lord in their forbidding to move freely.

When he finally arrives in Istanbul at the end of June, the intrigues led by his opponents, notably the future prince Vasile Lupu, did their job: the Ottoman government refuses to recognize him and condemns him to death.