Yim Si-wan (born Yim Woong-jae, December 1, 1988) is a South Korean singer and actor. He debuted as a member of the South Korean boy group ZE:A and its sub-group ZE:A Five. As an actor, he is known for starring in the film The Attorney (2013) as well as the television series Misaeng: Incomplete Life (2014) and Run On (2020). He gained international recognition for his role in the second and third seasons of Squid Game (2024–2025).