The purpose of the study is to determine the markers of immunosenescence in the diabetes 2 type. It was investigated the blood of 184 patients (age 50–90 years) by the method of polychrome flowing cytometry and enzyme immunoassay. By the method of cluster analysis the subpopulation of CD4⁺, CD8⁺ and the activated CD CD3⁺HLA^–DR⁺ T-cells (Tact) as the most informative indicators were selected. The groups of patients with uniform changes of this complex were formed. The groups included patients with the different stages of activation or deficit of CD4⁺ and/or CD8⁺. Tact values, which exceeded the norm, were identified with varying frequency in all age groups, including those with normal absolute number of CD4⁺ and CD8⁺. In this case detection rate was 100% (activation) and decreased to 33 % in immunodeficiency of CD4⁺ and CD8⁺. The proportion of individuals with activated immunity decreased with aging from 41 % (50–59 years) to 22% (80–90 years) and with immunodeficiency — increased from 43 to 75%, respectively. The chosen complex of indicators reflected the age-associated reaction of the T-cells in individuals to the chronic inflammation in diabetes type 2 and can be used as a diagnostic marker of the immunosenescence stage.