Kim In-seo (; born 11 January 1984) is a South Korean actress, best known for her portrayal of Se-jung in the 2010 action thriller film I Saw the Devil.
She is best known for her portrayal of Se-jung in the action film I Saw the Devil, which was censored thrice to get an adult rating in South Korea. In the international cut of the film, her sex scene with Choi Min-sik, which exposed her naked butt was cut, while at the same time being retained in the Korean cut.
She has also appeared in other Korean films like Children, Goodbye Mom and drama series like Flower Band, Vampire Prosecutor, Please Come Back, Soon-ae and The Musical.
Kim took a break from acting and married her non-celebrity boyfriend in September 2014. She gave birth to their two daughters, before returning to acting in 2020.