Choi Jung-yoon made her acting debut in the hit 1996 MBC sitcom Three Men, Three Women. In 2000, she acted alongside Kim Gyu-ri and Ha Ji-won in the horror film Nightmare, which earned her a Best Supporting Actress nomination at the 21st Blue Dragon Film Awards. In 2003, she joined the MBC series Attic Cat. In 2006, she appeared in director Lee Jun-ik’s dramedy Radio Star, which gave her Best New Actress nominations at the 27th Blue Dragon Film Awards and the 43rd Baeksang Arts Awards. In 2007, she was cast in tvN’s Romance Hunter and in the SBS dramas Bad Couple and That Woman Is Scary. In 2011, she and Ryu Soo-young were named Best Couple at the KBS Drama Awards for the family weekend series Ojakkyo Brothers. In 2012, she starred in the daily dramas Angel’s Choice and Be Strong, Mr. Kim, which aired on MBC and KBS1, respectively. In 2014, she led the cast of SBS’s Cheongdam-dong Scandal, which won her an Excellence Award at the SBS Drama Awards. In 2021, she made her small screen comeback through the SBS morning soap opera Amor Fati.

In 2011, Choi Jung-yoon tied the knot with Yoon Tae-joon, who is the eldest son of a high-ranking official of the South Korean conglomerate E-Land Group. Five years later, she gave birth to a daughter. In 2021, it was confirmed that the actress had filed for a divorce from her husband.