Jang started working as a child model at the age of five after he was discovered by a talent agent.
He announced that he will be selecting an "aggressive" range of movies and TV series to work on in 2016.
Jang made a successful comeback in 2016 with Mnet's music survival show Produce 101, where 101 trainee girls competing against each other for their debut.
In 2007, Jang was cast in the rock music-themed film The Happy Life, directed by Lee Joon-ik.
Jang then co-hosted SBS's weekly live music show Inkigayo from February 25 to October 7, 2007.
Jang made his acting debut in the 1997 HBS (now Channel CGV) sitcom Selling Happiness.