Family name Kvasnyak (Квасняк 
, Kvasnyak 
) , worldwide, is a rare surname. The cognomen Kvasnyak is characteristic of Ukraine, where it is a rare surname, Russia, where it is a very rare surname, and Spain.
| VARIANT | COUNTRY |
|---|---|
| Квасняк | Kazakhstan, Ukraine, Russia |
| Kvasnyak | Canada, Spain, Ukraine, Russia |