The material for the study was wood samples that were collected in the summer of 2021 on the coast of Heiss Island in the Franz Josef Land archipelago, in the Arctic Ocean. Heiss Island is located in the central area of the archipelago. The wood was 1) brought by the sea (“drift wood”) and was located on the shore at minor distances from the water line or 2) anthropogenic origin and was an external part of abandoned structures. As a result of investigations, we revealed complexes of microfungi on coniferous and deciduous wood, which include 30 species of microfungi, mainly from the Ascomycota division. Species of the genus Cadophora were found in the greatest number of examined samples. Indicators of species diversity and occurrence of representatives of the Basidio-mycota department were low. The yeast component (Ascomycota and Basidiomycota) accounted for 23% of the identified species. A total of 25 species were found in wood samples of anthropogenic origin and 12 species in drift wood samples. Studies of the enzymatic activity of microfungi showed that ligninolytic activity was noted in 50% of the strains studied, amylazolytic in 62%, and cellulolytic in 85% of the strains studied. A group of psychrotrophic species with high ligninolytic activity, together with cellulolytic and amylase activity, and well adapted to decomposition of wood substrate in the extreme conditions of the Arctic was identified. Activity profiles of different isolates of the same species do not always coincide and expression of individual enzymatic activity factors in many cases has a strain character.