The first discoveries of European pit vipers (Crotalinae gen. et sp. indet. A and B) are reported from the Ukrainian Miocene (MN 9a) locality of Gritsev. Based on perfectly preserved maxillaries, two species closely related to pit vipers of the 'Agkistrodon' complex are represented at the site. It is suggested that the European fossil representatives of the 'Agkistrodon' complex are Asiatic immigrants. Pit vipers probably never expanded into the broader areas of Europe during their geological history.