Surname Sopelniak (Sopelniak, Сопелняк 
, Сопельняк 
) , throughout the world, is a rare cognomen. The family name Sopelniak is habitual in Eastern Europe, particularly Russia, where it is a rare surname, Ukraine, and Belarus.
| VARIANT | COUNTRY |
|---|---|
| Сопелняк | Russia |
| Сопельняк | Kazakhstan, Russia, Kyrgyzstan, Belarus, Ukraine |