Surname Demyanyuk (Демянюк 
, Demyanyuk 
, Демьянюк 
) , throughout the world, is quite a rare last name. The surname Demyanyuk is characteristic of Eastern Europe, particularly Belarus, where it is quite a rare surname, Ukraine, and Russia, where it is a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Демянюк | Belarus, Russia, Kazakhstan, Ukraine |
| Demyanyuk | Spain, Bulgaria, United States, Russia, Ukraine |
| Демьянюк | Kazakhstan, Belarus, Kyrgyzstan, Russia, Ukraine |
| Демианюк | Russia |