He directed the Korean dramas War of Money (2007), Painter of the Wind (2008), Deep Rooted Tree (2011), My Love from the Star (2013-2014), Hyena (2020), and Lovers of the Red Sky (2021).

Jang reunited with Park in the period drama Painter of the Wind (2008), adapted from Lee Jung-myung's historical fiction novel that depicted the relationship between two Joseon era artists, Kim Hong-do and Shin Yun-bok (the latter is a woman disguised as a man, portrayed by Moon Geun-young).

For his next drama, Jang chose another Lee Jung-myung adaptation Deep Rooted Tree (2011), about a murder mystery surrounding King Sejong's invention of the Hangul system.

Written by Park Ji-eun (herself a hitmaker), the romantic-sci-fi dramedy about an alien who falls for a famous actress (played by Kim Soo-hyun and Jun) was popular domestically and overseas.

[5][6] The drama's massive success in the Chinese market[7] led to more opportunities for Jang, so he took a leave of absence from SBS, and signed an exclusive five-year contract with Yuehua Entertainment.