Surname Grubliak (Grubliak 
, Грубляк 
) , throughout the world, is a rare last name. The last name Grubliak is characteristic of Ukraine, where it is a rare surname, Lithuania, and Estonia. In absolute terms, it is the most numerous in Ukraine, Russia, and Lithuania.
| VARIANT | COUNTRY |
|---|---|
| Grubliak | Estonia, Spain, Lithuania, Ukraine |
| Грубляк | Russia, Kazakhstan, Ukraine |