Chae Jung-ahn landed her first television role in the MBC series Three Guys and Three Girls in 1996. In 2001, she headlined the KBS2 musical drama Mina. In 2004, she was cast in a major role in the KBS2 sageuk series Emperor of the Sea, which was nominated to the final round of the 2005 International Emmy Awards. In 2007, she starred in the hit romantic comedy Coffee Prince, in which she was nominated for an Excellence Award at the MBC Drama Awards. She and co-star Lee Seon-kyun were also nominated for the Best Couple Award for the chemistry they displayed on the series. In 2010, she received the PD Award at the MBC Drama Awards for Queen of Reversals. In 2015, she took home the Best Supporting Actress trophy at the 4th APAN Star Awards for the SBS medical romance Yong-pal. In 2016, she appeared in the SBS romantic comedy Entertainer, in which she was nominated for an Excellence Award at the SBS Drama Awards. In 2018, she picked up an Excellence Award at the 11th Korea Drama Awards for the Korean remake of the American legal series Suits.
As a singer, Chae Jung-ahn released three albums between 1998 and 2001. Her album called Cruel won her the New Artist Award at the 10th Seoul Music Awards in 1999.
Chae Jung-ahn married an advertising firm board member in 2005, but they divorced after only less than two years.