Born in Goyang City, Gyeonggi-do, South Korea, he was an only child. He attended Sewon High School and, at Konkuk University, he was a film major.
Before JB made his debut as a singer, he starred in the KBS drama Dream High as a backup dancer. He then landed the role of the main character in Dream High 2 alongside one of his group members, Jinyoung. Even after he made his debut as a singer, he starred in MBC's When a Man Falls in Love and in Naver TVCast's Dream Knight.
He won first place at a JYP open audition and was then given the stage name JB due to him sharing the same name as the famous singer, Yim Jae-Beom, who was his senior. With his group member Jinyoung, he made up the duo known as JJ Project. On the December 24, 2013, he and Jinyoung were made a part of the 7-member group GOT7. He became the group's leader and lead vocalist.
- He composed the song "Bad Behavior" for the album GOT ♡. He also contributed to the album Mad Winter Edition by writing the song "Everyday". He has also written and composed for Flight Log: Departure and Flight Log: Turbulence.
- His musical Inspirations are: Bruno Mars, Michael Jackson, India Arie, D'Angelo and Javier.
- He can speak some Japanese.
- He was involved in a minor car accident in 2014.
- He had a spinal disc injury that made him unable to participate in some of GOT7's Fly Tour concerts and an M!Countdown performance.