Last name Doyko (Дойко 
, Doyko 
) , across the world, is a rare surname. The surname Doyko is characteristic of Eastern Europe, particularly Bulgaria, where it is quite a rare surname, Ukraine, where it is a rare surname, and Belarus, where it is a very rare surname. Measured by absolute frequency, it is commonest in Eastern Europe, particularly Russia, Bulgaria, and Ukraine. Likewise, Doyko is the forename as well as the last name.