Surname Deminskii (Deminskii 
, Деминский 
) , all over the world, is a rare cognomen. The cognomen Deminskii is characteristic of Belarus, where it is a rare surname, Russia, and Kazakhstan, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Deminskii | Russia |
| Деминский | Kazakhstan, Russia, Ukraine, Belarus |
Деминський, and Дёминский