Yoo Yeon-seok (born Ahn Yeon-seok on April 11, 1984) is a South Korean actor.
After making his acting debut in 2003 with a small role in Oldboy, he resumed his acting career in 2008.
His notable works include the films Re-encounter (2011), Architecture 101 (2012), A Werewolf Boy (2012) and Whistle Blower (2014), Perfect Proposal (2015), Mood of the Day (2016) as well as the television series Reply 1994 (2013), Warm and Cozy (2015), Dr.