The analysis of changes in the specific immunity in patients with purulent—necrotic complications of diabetic foot syndrome (DFS) and sepsis was presented. Complicated DFS was diagnosed in 436 patients, of whom 29 (6.6%) — weighed down by sepsis. The concentration of the major classes of immunoglobulins IgA, IgM, IgG were determined by enzyme—linked immunosorbent assay (ELISA). To evaluate the immune state was determined lymphocyte subpopulations (CD4+, CD3+, CD8+, CD25+) with monoclonal antibodies to antigens use by flow cytometry. It was found that in patients with DFS indicators specific cellular immunity were in a state of suppression, which deepened at complication of sepsis. Based on the derived formula with DFS marked disorders of the immune system I degree, in sepsis — II degree. Thus, the cellular and humoral immune system in patients with both DFS and sepsis qualified as a general immune depression.