Objective. We aimed to analyze the alterations of activity of iron metabolism members i.e. ceruloplasmin (Cp) and transferrin (Tf), in relation to the percentage of glycated hemoglobin. The latter is one of biochemical criteria of chronic hyperglycemia compensation in case of type 2 diabetes mellitus. Materials and methods. Concentration and activity of Cp and Tf, concentration of iron, copper and lipoprotein cholesterol were measured by biochemical methods in blood serum samples obtained from healthy donors and patients with type 2 diabetes mellitus divided in three groups according to glycated hemoglobin level. Results. The significant decrease in serum copper, ferroxidase activity of Cp and iron-binding capacity of Tf, as well as an increase of Tf concentration, in groups with compensated and uncompensated type 2 diabetes mellitus was found. Conclusion. Our data demonstrate a statistical link between the degree of type 2 diabetes mellitus compensation and alteration of iron metabolism members’ activity. Th