The aim — to study qualitative and quantitative indicators of microbial decontamination using negative pressure therapy in patients with purulent‑necrotic lesions of diabetic foot syndrome.Materials and methods. 107 medical cards of inpatient patients were analyzed, which during 2015 — 2016 were on inpatient treatment in surgical department number 1 of the 2nd city clinical hospital in Poltava with various forms of purulent necrotic lesions of diabetic foot syndrome. Type 2 diabetes had 89 (83.2 %) people, type 1 — 18 (16.8 %). The quantitative and qualitative parameters of the rate of microbial purification on the basis of regular cultures from purulent wounds were determined.Results and discussion. Microbial contamination before the start of local treatment in both groups was 105 — 107.On the 10th day in the patients of the main group in the treatment of which vacuum therapy was used, microbial associations were not detected, aerobic monoflora was sown in 5 (9.1 %) people, including 3 (60.0 %) — S. epidermidis, 2 (40.0 %) — S. aureus with a microbial number of 103. In the same comparison group, where the local treatment was used the traditional approach to local treatment of monoculture was found in 18 (34.6 %) persons, microbial associations — in 14 (26.9 %) Complete cleaning of the wound from microbial contamination using vacuum therapy in the treatment of suppurative‑necrotic complications of the diabetic foot syndrome in patients of the main group occurred until the 10th day, in patients of the 14th day of comparison.Conclusions. In the study, the positive effect of the use of negative pressure therapy on the rate and effectiveness of wound healing from microbial contamination of purulent‑necrotic complications of SDS has been proved, which makes it possible to reduce the duration of the appointment period for antibiotic therapy in patients in the main group. The average period of inpatient treatment in the main group was about 12 days, in the comparison group — 17. Such indicators inversely proportional to the cost of treatment for purulent‑necrotic lesions of diabetic foot syndrome.