To assess the relationship between obesity and body fat distribution with cardiovascular risk factors in children, various measures of obesity and waist-to-hip circumference ratio (WHR) were related to serum lipids, lipoproteins, apolipoproteins, glucose, insulin, uric acid, systolic (SBP) and diastolic blood pressure (DBP). In boys univariate analysis revealed an association of triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (ApoB), the ratio ApoAI/ApoB, cholesterol/HDL-C, glucose and insulin to WHR. SBP and DBP and serum uric acid correlated with all measures of obesity [body mass index (BMI), percent overweight, percent body fat, skinfolds], but not with WHR. In girls lipid parameters (triglycerides, LDL-C, HDL-C, HDL2, ApoAI, ApoB) and atherogenic ratios correlated with measures of obesity and WHR. Glucose, insulin, SBP and DBP showed the highest correlation with WHR (r = 0.598, p less than 0.001 and r = 0.713, p less than 0.001). Multivariate analysis in girls revealed a first step dependency of ApoAI, the ratio cholesterol/ApoAI, insulin, SBP and DBP on WHR, triglycerides, HDL-C, LDL-C and the ratio ApoAI/ApoB, a first step dependency on percent body fat mass. In boys triglycerides, ApoB and the ratio ApoAI/ApoB were related to WHR for insulin, SBP and DBP, but a positive association with the WHR was found, explaining 33, 21.8, and 22.6% of the variance. This study demonstrates that cardiovascular risk factors in obese children are related to obesity and body fat distribution. Obese children with predominantly abdominal fat mass show a risk profile that is less favorable than gluteal-femoral fat distribution. Evaluation of body fat distribution in obese children, therefore, may help to identify persons most susceptible to cardiovascular risk in adulthood.