Abstract Introduction Non-HDL cholesterol (non-HDL) is recommended by NCEP ATP III (2005), its value correlates with level of apolipoprotein B and reflects the levels of all atherogenic lipid fraction. Non-HDL cholesterol is defined as the difference between the total cholesterol and the high-density lipoprotein cholesterol. Non-HDL cholesterol is better than LDL-Ch at predicting cardiovascular risk. Aim The aim of the study was to estimate the utility of non-HDL cholesterol in the obese children and adolescents fat metabolism. Material and methods The study population consisted of 306 children and adolescents of the ages 7–18 (13,1 ± 2,7) with simple obesity (SDS BMI ≥2). In each child there were estimated the anthropometrics measures, lipids profile, glucose metabolism. On account of the value of non-HDL the patients were divided into 2 groups: 1) 182 (60%) patients (♀ = 47%; ♂ = 53%) with elevated non – HDL (≥123 mg/dl); 2) 124 (40%) patients (♀ = 62%; ♂ = 38%) with normal non-HDL (<123 mg/dl). Results In children with elevated non-HDL we observed: higher mean waist circumference (91,2 cm vs. 94,1 cm; p = 0,04), mean levels of TC, LDL-Ch, TG, TC/HDL, TG/HDL and lower mean level of HDL – Ch against the children with normal non-HDL. In correlation study: with rising waist circumference increased the level of TG (r = 0,22; p = 0,001) and non-HDL (r = 0,11; p = 0,07), but decreased HDL-Ch (r = –0,11; p = 0,09). We found, that the increase of non-HDL was proportional to % correct body weight (r = 0,16; p = 0,01) i % FAT (r = 0,11; p = 0,08). Conclusion 1. Waist circumference is better parameter than SDS BMI in the estimation of lipids metabolism. 2. Non-HDL is dependent on abdominal obesity and is useful in the in the atherogenic lipoprotein estimation in children and adolescents with obesity.