This identifier is the first summary of the larvae of swamp mosquitoes (Diptera, Limoniidae, Pediciidae) of Russia. This group of diptera insects unites the largest families of long-winged dipterans and has more than 1700 species, of which at least half are registered in Russia. The presented monograph is based on original materials on the inhabitants of soil, wood and mushroom substrates, obtained as a result of many years of collection. The study considers mainly inhabitants of terrestrial environments, but the definition tables included some of the most studied genera in the literature, characteristic of the aquatic and semi-aquatic environment. For the first time, definitive tables of 2 subfamilies of Pediciidae and 3 subfamilies of Limoniidae, 7 tribes and 16 genera, including new morphological characters not previously known, are developed, information on the biology of representatives of more than 25 genera and descriptions of more than 60 species of larvae are given.