An analysis was carried of the fauna found in 338 beds from two old-age homes and from flats inhabited by asthmatic children. During hospitalization of these children the fauna in the flats was compared with that found in beds used by them in sanatoria. The most abundant species proved to be Dermatophagoides pteronyssinus that is also widely spread in other countries of Europe. The bed fauna in the sanatoria is very poor, corresponding to the improved state of health of patients during hospitalization. The authors assume that the low population density of fauna is influenced by constant airing of rooms and by strict separation of bedrooms from dining halls and other premises. Also the number of mites in different padding material used in mattresses was evaluated and an analysis of the general fauna per bed was carried out.