Choi Moo-sung landed his first feature film role in Birth of a Man in 2002 and has since appeared in several films and series. In 2006, he played a priest in the film Maundy Thursday. In 2010, he joined the cast of director Kim Jee-woon’s award-winning action thriller movie I Saw the Devil. In 2013, he portrayed a supporting character in the hit MBC sageuk Empress Ki. In 2015, he became part of the tvN series Answer Me 1988, which became one of the highest-rated shows in Korean cable television history. In 2016, he appeared in the film Snow Paths, which won him Best Supporting Actor at the 4th Wildflower Film Awards. In 2017, he acted alongside Park Hae-soo and Jung Kyung-ho in tvN’s Smart Prison Living, which was named Best Drama at the 12th Korean Cable TV Awards. In 2019, he starred in the mystery drama film Last Child, which score him acting nominations at the 6th Wildflower Film Awards and the 28th Buil Film Awards.

Choi Moo-sung completed his education at Tokyo Visual Arts.