Cognomen Мрочек (Мрочек 
, Mroček 
, Mrochek 
) , all over the world, is a rare surname. The surname Мрочек is habitual in Belarus, where it is a rare surname, Croatia, and Lithuania. In absolute terms, the name is most common in the United States, Belarus, and Russia.
| VARIANT | COUNTRY |
|---|---|
| Мрочек | Belarus, Russia, Ukraine |
| Mroček | Czechia, Croatia |
| Mrochek | Russia, Belarus, Canada, Lithuania, United States |
| мрочек, вацлав ромуальдович UA (b. 1897) |
|