The data on 79 species of aphyllophoroid fungi of the Mudyugsky Reserve, which is located near the mouth of the Northern Dvina River in the Primorsky District of the Arkhangelsk Region, are reported. Three species are new to the Arkhangelsk Region (Lindtneria leucobryophila, Peniophora piceae and Phlebia albomellea), all of them and Jaapia argillacea are known for the Arkhangelsk Region only from this area. Within the territory, there are three species listed in the Red Book of the Arkhangelsk Region and nine indicator species, of which seven are indicators of oldgrowth and two of virgin spruce and pine forests.