This revision is based on a comprehensive analysis of largely new, very extensive material encompassing 341 specimens (58 from Greece and 283 from Turkey). The type species Iurus dufoureius (Brullé, 1832) is restricted to Greece. Iurus asiaticus Birula, 1903 is confirmed as a distinct species, limited to eastern Anatolia. Most widespread in southern Turkey is another species, Iurus kraepelini von Ubisch, 1922, which is here restored from synonymy. We also describe two new species from Turkey: Iurus kadleci, sp. nov. from Antalya and Mersin Provinces (sympatric with I. kraepelini), and Iurus kinzelbachi, sp. nov. from İzmir and Aydın Provinces; therefore, fauna of Turkey includes four species of Iurus. Neotypes of I. dufoureius and I. kraepelini, and lectotype and paralectotypes of I. asiaticus are designated. Status of Iurus populations from the eastern Aegean islands of Greece (Fourni, Karpathos, Kasos, Rhodes, Samos, Saria) remains to be determined. A map of the distribution of Iurus is presented, based on 198 localities (79 in Greece and 119 in Turkey).