Parameters of the lipid metabolism and lipid peroxidation-antioxidant defense system in male adolescents with obesity, representatives of European and Mongoloid ethnicity were evaluated. Discriminant analysis revealed the most informative biochemical parameters for obese male adolescents: glutathione-S-transferase, VLDL cholesterol, glutathione peroxidase, reduced glutathione, and SOD activity for obese male Caucasian adolescents and glutathione-S-transferase, VLDL cholesterol, α-tocopherol, and glutathione peroxidase for Mongoloids obese male adolescents. The use of discriminant analysis allows implementing a differentiated ethnicity-oriented approach to prescribing antioxidant drugs in the complex therapy of obesity.