Born in
Seoul, Jang began his career with
Pohang Steelers, before joining Spanish side
Barcelona in 2011, following similar deals for compatriots
Lee Seung-woo and
Paik Seung-ho. These deals, along with multiple others, would cause Barcelona to be sanctioned by international body
FIFA in 2014, for breach of their rules regarding recruitment of youth players. Due to this, Jang was banned for three years, and briefly moved back to South Korea, along with Lee, to train with
K League 2 side
Suwon FC. In the summer of 2017, having failed to achieve promotion to Barcelona's
B squad, he was released. In February of the following year, he signed with
Pyeongtaek Citizen. Despite being a relatively bright player in Pyeongtaek Citizen's 8–0
Korean FA Cup loss to
Gimcheon Sangmu, he only managed a total of eleven appearances in 2021, scoring once. The following year, he played for both
Seoul Jungnang and Anseong Citizen. ==International career==