Kim Hye-yoon made her acting debut in the KBS2 TV Novel’s Samsaengi in 2013, which was followed by bit roles in a number of movies and TV series. She also appeared in several short films, which were shown at student film festivals. In 2018, she was launched into fame when she played the character of Kang Ye-seo in the mega-hit JTBC dark comedy series SKY Castle. Her work in the drama won her Best New Actress at the 55th Baeksang Arts Awards. In 2019, she landed her first leading role in the webtoon-based MBC series Extraordinary You, which was named Drama of the Year at the MBC Drama Awards. She also took home the Best New Actress trophy as well as an Excellence Award at the ceremony for her performance in the series. In 2021, she starred in tvN’s Secret Royal Inspector and Joy and in JTBC’s Snowdrop. In 2024, she acted alongside Byun Woo-seok in the popular tvN time-slip romance series Lovely Runner.

Kim Hye-yoon was a full scholar at Konkuk University. She graduated in 2019 with a degree in film studies.