She is best known for her portrayal of male character Baek Seong-woo in 2022 Netflix-produced South Korean drama Juvenile Justice.

[2] Lee Yeon first made her debut as an actress in 2018 with South Korean film Anonymous.

She has appeared in several films and television series, including a cameo as the younger sister of male lead Jung Hae-in's character in South Korean Netflix drama D.P.

[3][4] Lee's breakout role comes from 2022 Netflix drama Juvenile Justice, in which Lee's character is a 13-year-old male teenager Baek Seong-woo, who was charged with murdering a young schoolboy in the drama's first two episodes.

Despite being a female and her Korean age of 28 at the time she portrayed Seong-woo, Lee's acting and transformation as a cold-blooded murderer was positively reviewed and applauded by audiences and critics.