On islands in the northern part of Lake Ladoga, within the Republic of Karelia, 234 species of aphyllophoroid fungi have been recorded, including 4 species (Athelia alnicola, A. salicum, Botryobasidium pruinatum, Hypochnicium lundellii) new for the Republic. Data are provided on the distribution of 22 species new for Karelia ladogensis province, including Punctularia strigosozonata, red-listed in the Republic of Karelia (2007). Specimens of all the new records are kept in the mycological herbaria of the Karelian Research Centre (PTZ) and Komarov Botanical Institute RAS (LE). 198 species were found in the Nature Park Valaamsky Archipelago, 97 - in the Nature Reserve Zapadny Archipelago, and 43 -in the National Park Ladoga Skerries. A majority of aphyllophoroid fungi on islands in the northern part of Lake Ladoga were found on deciduous trees (109 species), 84 species were recorded on coniferous trees. Most of the species were collected from the main stand-forming species: 68 species from pine, 56 - from aspen, 51 - from spruce, and 47 - from birch. Fewer species were found on alder (25 species), willow (19), rowan (16), juniper (11), bird cherry (4), and on introduced tree species (larch, Siberian pine, maple, oak) on Valaam Island. Locations of 12 species protected in the Republic of Karelia (2007), and 3 species protected in the Russian Federation (2008), as well as of 19 indicator species of old-growth forests and 6 indicator species of pristine forests were found on the islands. The species richness of aphyllophoroid fungi on each island is depends on the typological composition and age of forests, presence of deadwood in different stages of decay, forest cover (rockiness), and anthropogenic disturbance, while the island size is not significant.