Petru (Peter) II Muşat (d. 1391) was Voivode (prince) of Moldavia from 1375 to 1391, the son of an unknown son of Bogdan I, the first ruler from the dynastic House of Bogdan, succeeding Laţcu, Bogdan's son and successor who converted to Catholicism .
During his reign, he maintained good relationships with his neighbours, especially Poland.
On 27 September 1387 at Lwów, he paid homage to the Polish king Władysław II Jagiełło, making Moldavia a Polish fief (which it remained until 1497). In 1388, he received Pokuttya as a pawn for 3,000 silver rubles he lent to the Polish king. Petru also acted as an intermediary in the negotiations between the Wallachia voivode Mircea cel Bătrân and the Polish king that resulted in the treaties signed by the two parties in 1389 and 1390. The first Russian-Moldavian diplomatic contacts also date from his reign.
He was married twice. From his first wife he had a son, Roman. In 1388 he remarried to Olga, daughter of Janusz I, Prince of Masovia. From his second wife he had another son, Ivaşcu.
Petru founded the Neamţ citadel and Neamţ Monastery, and built the Holy Trinity Church in Siret. He also fixed the princely seat of Moldova at Suceava in 1388, effectively dooming the Latin Diocese of Siret in the old capital, and maintained Orthodox Bishop Iosif at Cetatea Albă, contrary to the wishes expressed by the Patriarchate of Constantinople, resulting in his excommunication.