Family name Younsuk (Younsuk 
) , across the world, is a very rare cognomen. The surname Younsuk is habitual in Thailand, where it is a very rare surname, and China, where it is an extremely rare surname. Predominantly, Younsuk is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Younsuk | United States, Thailand, South Korea, China |