Surname Косян (Косян 
, Kosyan 
, Kosjan 
) , in the entire world, is quite a rare last name. The family name Косян is habitual in Armenia, where it is quite a rare surname, Russia, and Ukraine, where it is a rare surname. Very seldom, Косян is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Косян | Kazakhstan, Belarus, Armenia, Russia, Ukraine |
| Kosyan | Belarus, Armenia, United States, Russia, Indonesia |
| Kosjan | Hungary |
| косян мария викторовна UA (b. 1992) |
|