Kim Jae Joong (김재중; also known mononymously as Jaejoong and as J-Jun in Japan) is a South Korean singer-songwriter, actor, director, and designer. He is a member of the boy group JYJ and a former member of TVXQ!.
Kim Jae Joong was born Han Jae-joon; his real birthday, as revealed by his birth mother, is February 4, 1986. At a young age, he was given up for adoption by his biological mother to the Kim family, and his name was legally changed to Kim Jae-joong. Kim acknowledges January 26, 1986 as his official date of birth.