2017: W PROJECT and Golden Child
On March 31, 2017, Woollim had revealed the second unit for the W PROJECT. The unit was a rap unit that consisted of Jangjun and another member, TAG.
He was introduced as a member of Golden Child through the reality show 2017 Woollim Pick. He officially debuted with the group on August 28 with the release of their first mini album Gol-Cha! with "DamDaDi" as the title track.
- 2017 Woollim Pick (Mnet, 2017)
- His jersey number is 82.
- He has a dog named Maroo.
- Jangjun is friends with Woong.
- Jangjun’s role model is Bang Yongguk and he can also imitate his voice.
- He is the animal lover of the group.