In a first list of chironomid species from Italy from 1988, 359 species were recognized. The subfamilies represented were Tanypodinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae. Most of the species were cited as widely distributed in the Palearctic region with few Mediterranean (6), Afrotropical (19) or Panpaleotropical (3) species. The list also included five species previously considered Nearctic. An updated list was thereafter prepared and the number of species raised to 391. Species new to science were added in the following years further raising the number of known species. The list of species known to occur in Italy is now updated to 580, and supported by voucher specimens. Most species have a Palearctic distribution, but many species are distributed in other biogeographical regions; 366 species are in common with the East Palaearctic region, 281 with the Near East, 248 with North Africa, 213 with the Nearctic, 104 with the Oriental, 23 species with the Neotropical, 23 with the Afrotropical, 16 with the Australian region, and 46 species at present are known to occur only in Italy. On the basis of new findings in Italy and in nearby areas it is stated that the knowledge of chironomid fauna is still incomplete.