The paper discusses the structural features of micromycete communities on monuments of various types of stone in Saint Petersburg. It has been shown that the groups of dominant species are generally similar on the different rocks used to create the monuments. Peculiarities of fungal diversity in lithobiont communities are mainly asso-ciated with rare and random species. Carbonate rocks were characterized by a higher diversity of micromycetes than silicate rocks. Identified 90 species of micromycetes, the vast majority of which are anamorphic ascomyce-tes. Differences in the content of organic substances in biofilms and stratifications on the stone surface have little effect on the formation of groups of dominant and frequently occurring species, but are consistent with the structural features of micromycete complexes in the studied habitats. The presence of calcium oxalates in the studied samples of damaged stone proves the role of microorganisms in the processes of modern mineral formation.