Abstract. The vast majority of these midges. (Simuliidae) is the bloodsuckers of humans and domestic animals. On the vast territory of Russia and the CIS, in the steppe, forest-steppe and especially in the taiga and tundra, midges occupy one of the first places among the blood-sucking Diptera. The family of blood-sucking midges is represented in Russia by more than 300 species. There are numerous midges in the valleys of large rivers with clean fast flowing water; their number is especially high in the taiga zone – in the valleys of the large rivers of Siberia and, to a lesser extent, the European part. On the territory of Russia moshki are found everywhere, but their abundance decreases from North to South. The zone of taiga and deciduous forests is most rich in them.