[in Russian with English abstract: ] Alexander Alexandrovich Elenkin is considered as the founder of the Russian lichenological school and one of the founders of other areas of cryptogamic botany in Russia — algology, mycology, phytopathology, and bryology. Elenkin was born 150 years ago in Warsaw, but almost all his life since 1898 he worked at the Botanical Institute in St. Petersburg. Elenkin has created the Cryptogamic Herbarium, in the walls of which brilliant scientists, specialists in various fields of cryptogamic botany grew up under his leadership. The life of the talented and enthusiastic scientist, teacher and organizer, who devoted himself entirely to science, was not easy, especially at the end, and tragically ended in 1942 in Kazan. Keywords: algology, bibliography, bryology, Cryptogamic Herbarium, Elenkin, history of science, Komarov Botanical Institute, lichenology, mycology, phytopathology, Russia.