For the first time a mycological analysis of dust, including assessment of the proportion of opportunistic species in the air-green infrastructure-paved surface systems, was carried out in cities of different climatic zones (Mur-mansk and Moscow). The complex influence of factors (climate, city functional zone, collection matrix type) on quantitative and qualitative parameters of fungal communities was assessed on the basis of multivariate analysis. A lower abundance of cultivated mycobiota in the air, on leaves and paved surfaces was found in Murmansk compared to Moscow. However, about half of the identified species in both cities were considered as opportunistic. An increase in the proportion of the most dangerous group of opportunistic fungi BSL2 in the air of the transport zone was noted in both cities and in the residential zone in Moscow. In Moscow microscopic fungi Aspergillus fumigatus, A. niger prevailed in abundance in the air and on the paved surface in the residential and transport zones, while in Murmansk representatives of less pathogenic for humans genera Cephalosporium, Scopulariopsis, Trichoderma dominated. Substrate type (air, leaves, paved surfaces) and climate had the greatest influence on the abundance and species diversity of micromycetes, including conditionally pathogenic species, while functional zone had no significant influence. The recreational zone of both cities in different climatic zones was the most favorable for human residence because of the lower number of opportunistic species in the air and the absence of microscopic fungi of the most dangerous groups BSL-2 and BSL-3. However, a higher number of potentially pathogenic species have been identified on leaf and road surfaces in this zone in both cities compared to the air. This makes it possible to recommend that urban dwellers minimize contact with plant leaf surfaces and hard surfaces on roads, which is particularly relevant for pre-school children, in order to reduce the likelihood of interaction with opportunistic mycobacteria as potentially dangerous to human health. © 2021, Russian Academy of Sciences. All rights reserved.