The European species of the potter wasp genus Eumenes Latreille, 1802 ( Vespidae , Eumeninae ) are illustrated and a new illustrated key to the 13 recognised species is presented. Eumenes mediterraneus aemilianus Guiglia, 1951 is synonymised with E. papillarius (Christ, 1791) ( syn. nov.), E. obscurus André, 1884 and E. andrei Dalla Torre, 1894 with E. pedunculatus (Panzer, 1799) ( syn. nov.) and E. crimensis Blüthgen, 1938 with E. sareptanus André, 1884 ( syn. nov.).