| Yi Jeong, Crown Prince Uiso 이정 의소세자 | |
| Succession: | Crown Prince Successor of Joseon |
| Successor: | Crown Prince Successor Yi San |
| Father: | Crown Prince Sado |
| Mother: | Crown Princess Consort Hyegyeong of the Pungsan Hong clan |
| Birth Name: | Yi Jeong |
| Birth Date: | 27 September 1750 |
| Birth Place: | Changdeok Palace, Hanseong, Joseon |
| Death Place: | Changdeok Palace, Hanseong, Joseon |
| Royal House: | House of Yi |
| Hangul: | 의소 세손 |
| Rr: | Uiso Seson |
| Mr: | Uiso Seson |
| Hangulborn: | 이정 |
| Rrborn: | Yi Jeong |
| Mrborn: | Yi Chŏng |
Crown Prince Uiso (; 27 September 1750 – 17 April 1752) or Crown Prince Successor Uiso, personal name Yi Jeong was a Joseon Crown Prince as the son of Crown Prince Sado and Crown Princess Consort Hyegyeong and was third in line of succession to the throne to King Yeongjo. He was the older brother of King Jeongjo. His Chinese name was Changheung .[1]
His mother, Lady Hyegyeong, of Pungsan was from a famous royal family line. His maternal grandfather was Hong Bong-han, whose younger brother was Hong In-han, a minister and later Prime Minister of that time.
He was the first grandson of the 21st King Yeongjo of Joseon and his father, Crown Prince Sado, was the illegitimate second son of King Yeongjo. King Yeongjo's first son, Crown Prince Hyojang, died at the age of 10, leaving Crown Prince Sado as King Yeongjo's only male descendant. King Yeongjo hoped for another son but instead bore only daughters.
Uiso's father Crown Prince Sado had a severe mental illness and was often at odds with his father, King Yeongjo. Crown Prince Sado favoured the political party Soron, while King Yeongjo supported the ruling party Noron. Later King Yeongjo had his son, Crown Prince Sado, executed by locking him in a rice chest and starving him.
On September 27, 1750, he was born in Gyeongchungung, Changgyeong Palace, Hanseong, Joseon. On May 13, 1751 King Yeongjo declared him the political heir.
In November 1751, his aunt Lady Hyeonbin died, then soon after on 17 April 1752, Crown Prince Uiso died Tongmyongjeon. His grandfather, King Yeongjo took the deaths hard and severed from psychological trauma for some time.
He was given a state funeral,[2] from special instructions of King Yeongjo. His body was buried to the south of Mt. Ahnhyon (안현 鞍峴), Bugahyeon-dong in Hanseong.[3] King Yeongjo named his grave Uiso grave and wrote the epitaphs, erecting a tombstone.
In 1870, his grave name was Uiryong Park .[4] On June 7, 1949, his grave was moved to Wondang in Goyang.