Queen Munjeong, of the Papyeong Yun clan, was a posthumous name bestowed to the wife and third queen consort of Yi Yeok, King Jungjong. She was Queen consort of Joseon from 1517 until her husband's death in 1544, after which she was honoured as Queen Dowager Seongryeol during the reign of her step-son, Yi Ho, King Injong. She was honored as Grand Queen Dowager Seongryeol during the reign of her son, Yi Hwan, King Myeongjong.
Queen Munjeong acted as regent during the minority of her son between 1545 and 1565. She was an effective administrator and the most influential supporter of Buddhism during the early Joseon dynasty. She gave out the land to the common people that had been formerly owned by the nobility. During her regency, her brother, Yun Won-hyeong, wielded enormous power to wipe out their opposition and led the Fourth Literati Purge of 1545.