Abstract. Aim. Study of biological diversity of the Caspian and island ecosystems, the composition, especially the geographical distribution and possible ways of forming a scoop fauna (Lepidoptera, Noctuidae) are presented.

Methods. We used the traditional methods of collecting (light traps, hand picking from the screen), and the definition of material processing. List of species composition of discussed fauna composed by modern taxonomy using directories is presented.

Results. 40 -years study of the authors (islands ecosystems are discussed at the first time), and published works of other researchers are summarized. Fauna of Caspian coast and islands ecosystems is represented by 902 species (Chechen Island – 82 species, Tyuleniy Island – 59, Nordoviy Island – 21, Kulaly Island – 28). Fairly well represented on the mainland genera (Cuculia – 64, Acronicta –28, Caradrina – 24, Hadena – 31, Euxoa – 51, Xestia – 63, etc.) have from 1 to 5 species on the islands. Cornutiplusia circumflexa (Linnaeus,1767), Photedes extrema (Hübner, 1809), Pseudohadena immunda (Eversmann, 1842 ), Hadena capsincola (Denis & Schiffermüller, 1775 ) are found only on the islands, and Turkmen species, genus and subfamily has not been which were not found in the south-west of Kazakhstan is found on Chechen Island. Analysis of areas of discussed fauna showed a clear dominance Turanian, Mediterranean, Trans-Holarctic complexes. Established relationship and power links 13 regional and island faunas five Caspian countries.

Main conclusions. The results obtained in the amount of the other groups of insects, arachnids, animals and plants form the basis of findings of probable ways of formation of these faunas, the age of the islands themselves, and most importantly the level regime of the Caspian Sea.