He then continued to work in television as a child actor.
Studying in New Zealand at the time, a role in the popular MBC sitcom Nonstop 4 brought him back to South Korea.
He said, “My mother has once said that she really like Park Shin Hye, who lives in the same neighborhood.
In 2005, Jang played the president's son in the SBS drama Lovers in Prague.
In 2006, Jang debuted on the big screen in the Japanese horror film One Missed Call: Final where he played the role of a deaf boy.
Under this situation, I really liked Ha Ji Won noona during the drama filming.” He also confessed, “Not just that, I felt really excited when I did the kiss scene with Sung Yuri noona in drama ‘Hong Gil Dong’.” Meanwhile, during the show, Jang Geun Seok showed the nervous side of him while having to choose between actresses like Ha Ji Won and Sung Yuri for his ideal women.
Up til now, there hasn't been any proper talk about a season 2.