Last name Grynchyshyn (Гринчишин 
, Grynchyshyn 
) , around the world, is quite a rare cognomen. The last name Grynchyshyn is habitual in Eastern Europe, particularly Ukraine, where it is quite a rare surname, Slovakia, where it is a rare surname, and Belarus. Not in comparison with a country's population, the name is most common in Eastern Europe, particularly Ukraine, Russia, and Slovakia.