Surname 성윤 (성윤 
, Sung-Yoon 
, Seong-Yun 
) , around the world, is a very rare family name. The cognomen 성윤 is habitual in China, where it is an extremely rare surname, and the United States. Much more frequently, 성윤 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 성윤 | South Korea |
| Sung-Yoon | United States, South Korea, Canada |
| Seong-Yun | United States, China |