Queen Jeonghui (Hangul:정희왕후, Hanja:貞熹王后) (8 December 1418 – 6 May 1483) also known as Queen Dowager Jaseong (자성왕대비) was Queen Consort to King Sejo of Joseon and the mother of Sejo's successor King Yejong of Joseon. Following her husband's death in 1468, she served as regent for her weak son from 1468 to 1469 and co-regent for her young grandson from 1469 to 1477, along with her daughter-in-law, Grand Queen Dowager Insu. She was from the Papyeong Yun clan.

Queen Jeonghui was born on the eleventh day of the eleventh lunar month in the eighteenth year of King Taejong's reign. Her father Yun Beon (Hangul: 윤번, Hanja: 尹璠) (1384–1448) would later become Prime Minister. Her mother was Yun Beon's wife Lady Lee (Hangul: 이씨, Hanja: 李氏). She married the then-Grand Prince Suyang in 1428, on the thirteenth day of the twelfth lunar month in the tenth year of King Sejong's reign. She became Queen consort upon her husband's accession to the throne in 1455.

Queen Jeonghui became regent when her son, Yejong of Joseon ascended to the throne in 1468, because he was physically ill. According to records of this era, political decisions were taken by the Queen and three subjects nominated by King Sejo.

In 1469, King Yejong died at the age of 20 and was succeeded by his nephew, Queen Jeonghui's grandson King Seongjong. As Seongjong was only 13 at the time of his accession, Queen Jeonghui ruled the nation in Seongjong's name along with her daughter-in-law, Seongjong's, Queen Insu (whose husband had never actually been king). During her regency, common farmers were granted the right to cultivate fields that had originally belonged to the military. In 1474, the code of law, first ordered by King Sejo, was completed and put into effect.

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