Examination of river basins of Yakutia and the study of the previously collected material resulted in revealing of 34 species of the subfamily Prosimuliinae belonging to 8 genera (Gymnopais, Prosimulium, Helodon, Stegopterna, Greniera, Cnephia, Metacnephia, and Sulcicnephia). The fauna of Yakutia was supplemented with two black fly species Cnephia angarensis Rubzov, 1956 and Gymnopais frontatus Yankovsky, 1982. The distribution of the species Prosimulium tridentatum, Helodon alpestris, H. irkutensis, H. rubicundus, Stegopterna asema, and Cnephia lyra) was clarified. The combined table of species distribution with GPS coordinates of collecting sites has been composed.