The objective of the present study was to analyse dynamics of the serum adiponectin levels during treatment of obesity in the adolescents. A total of 34 patients at the age varying from 12 to 17 years presenting with "simple" constitutional exogenous obesity were available for observation. All of them had metabolic complications, such as impaired glucose tolerance, insulin resistance, dyslipidemia, and arterial hypertension. A course of motivational education for the change of lifestyle was provided to 15 patients and their parents in combination with healthy diets, physical activities, and orlistat intake (120 mg, one capsule thrice daily) during 6 months. The patients of the control group (n=19) were given non-medicamental therapy alone. The effectiveness of therapy was estimated before, 6 and 12 months after its initiation. The combined treatment of complicated obesity in the adolescents was shown to promote a decrease of the body weight by 0.04-0.08 SDS of MBI within one year after the onset of therapy. Simultaneously, the degree of dyslipidemia, insulin resistance, and disturbances of carbohydrate metabolism was reduced whereas the serum adiponectin levels increased. The study failed to reveal advantages of orlistat treatment for the reduction of BMI. At the same time, the introduction of this medication into combined therapy of obesity in adolescents resulted in a clinically significant decrease of the frequency of dyslipidemia, largely due to lowering the total cholesterol and LDLP cholesterol levels. Orlistat therapy was well tolerated by the patients. Variations in the adiponectin level were in agreement with body weight dynamics and changes of insulin resistance. It is concluded that low serum adiponectin levels in association with the high frequency of complications may suggest high risk of progression of metabolic disturbances in obese adolescents towards adulthood.