A former South Korean international in mid-1980s, Jang Jung had a brief playing spell with Perak before switching over to be part of Singapore's Dream Team, which eventually won the League and Cup double in 1994.
After the withdrawal from the Malaysian competitions, Jang Jung returned to Korea before making a return to the S.League with Geylang United. He would also go on to coach the side for four years.
Prior to his appointment by the Perak FA, Jang Jung was coaching in Sri Lanka for six years, beginning with the Under 23 side and moving on to the senior team in 2007.
Perak FA president Datuk Zainol Fadzi Paharudin confirmed on Wednesday that the Korean had signed a three-month contract to lead the team at the Malaysia Cup.
Norizan Bakar, the man Jang Jung replaces, has been given a leave of absence and no further details on his future have been revealed.
Despite a strong start to the season, Perak faded away in the latter stages of the competition and finished fourth in the Malaysian Super League, some way off from champions Kelantan and runners-up LionsXII.
The Malaysia Cup will commence in late July.