Family name Ергюн (Ergyun 
, Ергюн 
, Ergioun ) , in all the world, is a very rare last name. The last name Ергюн is habitual in Bulgaria, where it is a rare surname, Greece, where it is a very rare surname, and Ukraine. Not in comparison with a country's population, this name is the most popular in Eastern Europe, particularly Bulgaria, Ukraine, and Russia. Also, Ергюн is the forename as well as the last name.