Kang Sung Hoon (born February 22, 1980) is a vocalist formerly from the group Sechs Kies. He was the lead vocalist of Sechs Kies and sometimes referred to having the best singing voice like Kangta's voice. After Sechs Kies had ended, Kang Sung Hoon was considered to be born-again as a singer, and working under Laful Entertainment, but now is working for NH Media Entertainment. There were some little rivalry as Sung Hoon released 4 albums, as the leader of Sechs Kies did; Eun Ji-won. He served military time along with Lee Jae-jin,also a Sechs Kies member in 2006. In 2002 Dynamic Korea, he performed on stage with Eun Ji-Won, and also J-Walk, the duet consisting of 2 former Sechs Kies members Kim Jae-duc and Jang Su-won. On January 22 of 2007, Kang Sung Hoon participated in a fashion show called "Han Bok" which is to raise money to build homes for others. His nickname Hoony is the title for his 3rd album. Sung Hoon is currently in military training and will return during April.