Yoon Shi-yoon (Korean: 윤시윤; born Yoon Dong-gu on September 26, 1986) is a South Korean actor and television personality. He is best known for his leading roles in King of Baking, Kim Takgu (2010), My Cute Guys (2013), Hit the Top (2017), Grand Prince (2018) and Your Honor (2018). The Nokdu Flower (2019), Psychopath Diary (2019-2020). In 2016, he became a member of the variety show 2 Days & 1 Night.
Yoon was born Yoon Dong-gu, a name he used until an official change of name upon his entry into college, in a small town in Suncheon. He is the only child of his family, and was raised by his grandparents. At the time, while peers of his age went to kindergarten and learned English, Yoon went to seodang, a traditional school that taught Confucianism, and learned to read Hanja (Chinese characters). Yoon's unique childhood was then unveiled through his song "Grandpa's Bicycle" for Barefooted Friends.