Jin Woon was born on May 2, 1991 in Seoul, South Korea. He graduated high school from BaekAhm High School. He, along with Shinee's Onew and Girls' Generation's SeoHyun, had the highest national score for their high school SATs exam. He studied at Daejin University, Dept. of Theatre and Visual Arts, the same class as fellow group member, Seulong. Jinwoon is known to be close to 91-liners, such as Nicole Jung of Kara,Son Dong-woon of Beast, Mir of MBLAQ, Key of Shinee, and SeoHyun of Girls' Generation. On October 7, 2013 he suffered a car accident and went into surgery. The surgery went well and currently he is going through a recovery process.
He was originally eliminated from 2AM in the Hot Blood documentary, Jinwoon returned after a chosen member Daehun had to return to the States for personal reasons. Prior to debut, he was in a band called "No Comment". He plays guitar, drums, bass guitar, bongo and piano.
On August 7, 2011, the music video of his first solo single, "You Walking Towards Me" was released by Big Hit Entertainment. Jinwoon wrote and composed the song. It also features mixing by engineer Michael Brauer, who’s previously worked with the likes of U2 and Coldplay. Jinwoon held his debut stage last month at the Jisan Valley Rock Festival, where he performed “You Walking Towards Me”. His limited single (1,000 copies). It went on sale on August 4. Also included in the single album was another song he composed, "Lalala".
This was followed by another two-single mini album, which includes the songs "Now or Never" and "Psycho", which he both wrote too. On November 8, Jinwoon pleased the fans by allowing his song "Psycho" to be downloaded for free. The album and music video were released November 17.
On November 25, he held his first solo concert at Hongdae V Hall in Seoul. To help establish his ‘rocker roots’, he received mentorship from veteran rock band YB, vocalist Yoon Do Hyun, and bassist Park Tae Hee. Big Hit Entertainment revealed on November 15, “Jinwoon successfully completed a joint production with Yoon Do Hyun’s Band, who he’s admired for a long time. Through his concert, Jinwoon will deviating from his 2AM image to show a new “rocker” side to his personality.”