Abstract— <p>Rapid climate warming in the Arctic contributes to an increase in the number of fungal species. However, the long-term dynamics of alien mycobiota, especially in Siberia, has been studied fragmentarily. In one of the largest industrial centers of the Arctic, the Norilsk city and nearby settlements in the Taymyrsky Dolgano-Nenetsky District of Krasnoyarsk krai, 78 species of fungi and pseudofungi (Ascomycota, Basidiomycota, and Oomycota) have been collected on alien plants over a 100-year period. Of these, 59 species are new to the district, 32 of which are noted in the Russian Arctic for the first time. Fungi are associated with 57&#xa0;species of alien woody and herbaceous plants, 8 of which are included in the Black Book of Siberian Flora; 50 species of fungi were found on woody plants and 38 on herbaceous plants. The richest mycocomplexes are associated with <i>Populus tremula</i> (seven species of fungi), <i>Acer negundo</i>, and <i>Prunus padus</i> (five species each). Most of the alien fungi species (69.2%) are taxa widespread in Siberian forests, which, thanks to alien host plants, were able to expand their range to the north, while 7.7% are invasive for the entire territory of the Arctic and Siberia. The primary ranges of 24 fungi species are located in America, East Asia, and Europe. All alien fungal species were brought to district unintentionally. The main vectors of dispersal are the development of transport infrastructure and the movement of transport, people, and related goods during the economic development of territories. The first results indicate the absence of a correlation between the number of aphyllophoroid fungi species with the age and area of cities, but a reliable relationship has been established with the number of residents. A detailed study of other territories will allow the development of a Black List of Russian Arctic mycobiota.</p>