Kim Min-jung started acting when she was six years old and went on to become one of the most sought-after young stars of her time. She proved her acting skills early on in her career with Best Young Actress wins at the 1992 and 1998 KBS Drama Awards. She successfully transitioned into mature roles with appearances in the dramas Rival and Ireland, in which she took home acting recognitions. In 2008, she received a Golden Acting Award at the MBC Drama Awards for her work in the medical drama New Heart. In 2015, she was cast in the KBS2 novel-based sageuk Master of Trade—Inn 2015, which earned her two Excellence Awards. In 2018, she won Best Supporting Actress for her performance in the hit tvN series Mr. Sunshine. In 2019, she starred in the KBS2 drama My Fellow Citizens as a daughter of a notorious loan shark. She bagged a Top Excellence Award at the 12th Korea Drama Awards for the series. In 2021, she reunited with her New Heart co-star Ji Sung for the first time in 13 years in the tvN legal drama The Devil Judge.

During a guesting on KBS2’s Happy Together 3 in 2012, Kim Min-jung revealed that she had secretly dated a celebrity for two years.