Twenty-seven mite species belonging to 23 genera, 13 families, and 2 orders were identified. The mites of the family Pyroglyphidae, amounting to 91.1% of the total number of mites, were found to dominate in the acarocomplex of Penza dwellings. Pyroglyphid mites were represented by 3 species with Dermatophagoides pteronyssinus and Dermatophagoides farinae absolutely prevailing in both their abundance (20.0 and 68.5%) and frequency (39 and 75%). The maximum number of D. pteronyssinus and D. farinae reached 2.867 and 3.400 mites per g of dust, respectively. Mites of the families Acaridae and Glycyphagidae were registered in 27 and 15% of the apartments, respectively; and their abundance was about 4%. G. destructor is most frequently encountered. The specific abundance and detection rate of other mites were not high. The influence of various socioeconomic factors on the number of D. pteronyssinus and D. farinae was analyzed using statistical methods. A significant correlation was found between the number of mites, the air moisture of a premise, the building material used for the construction of a house, the type of a housing estate (a private or tenement house) and heating (central or self-contained). No significant relationship was established between the number of mites, the ventilation of premises, the presence of domestic animals and plants or flowers, and the number of dwellers. Out of 81 patients with allergic diseases (allergic rhinitis (73%), bronchial asthma (4%), and allergic rhinitis concurrent with asthma (23%)), 44 and 25% patients had positive skin tests for D. pteronyssinus and allergens of D. farinae, respectively. There was no positive correlation between the number of pyroglyphid mites, positive skin tests, and the diagnosis.