Jung Moon-sung debuted as an actor in 2007 with the musical Subway Line 1 before extending his career to television and film. In 2012, he played a supporting character in the SBS series Ghost. He also had appearances in JTBC’s Heartless City in 2013 and in the SBS sageuk Six Flying Dragons in 2015. In 2018, he was cast in a number of TV series such as tvN’s About Time and JTBC’s Life. In 2019, he joined the main cast of SBS’s Haechi, which won him the Best Character Award at the SBS Drama Awards. In 2020, he became part of the hit tvN drama Hospital Playlist and also returned for its second season. He then acted alongside Namgoong Min in the 2021 MBC action thriller The Veil. That same year, he starred in its two-part spin-off series Moebius: The Veil, which earned him an Excellence Award at the MBC Drama Awards.