FIELD : medicine.SUBSTANCE : invention relates to microbiology. Method of biological disinfecting cleaning and disinfection of bacteria and viruses from the premises of medical institutions from pathogens involves the processing of these premises once a day with a solution of the CHRISAL probiotic preparation. Swabs in various places of the premises are collected and sowed on nutrient media monitoring the current cleanliness of the premises. Sowing of swabs is carried out on nutrient media no earlier than five hours after each treatment with the CHRISAL probiotic preparation, and the duration of the cleaning and disinfection process is 10 days. Treatment of the premises in the first days is carried out with a 5?% aqueous solution of the CHRISAL probiotic preparation, brought to 40?癈, and the next five days with 1?% aqueous solution of the CHRISAL probiotic preparation, brought to 40?癈.EFFECT : invention makes it possible to increase the microbiological purity of the environment of the premises of medical institutions.1 cl, 1 tbl