Family name Kostetski (Kostetski 
) , globally, is a very rare surname. The last name Kostetski is habitual in Greece, where it is a very rare surname, Germany, where it is an extremely rare surname, and Canada. In absolute terms, it is the most numerous in Greece, Germany, and Russia.
| VARIANT | COUNTRY |
|---|---|
| Kostetski | Russia, Ukraine, United States, Germany, Greece |