In order to investigate the relationships of obesity in childhood to plasma lipid, blood pressure and blood glucose concentration, we selected 21 subjects for the moderate obese group(MO), 9 for mild obese group(MI), and 19 for the control group(C) among children aged 10~12. While the level of plasma triglyceride and VLDL-cholesterol of the MO group was much higher than that of group C, a significantly lower percentage of HDL-cholesterol was found in the MO compared to the percentage found in group C. Also the level of the total cholesterol and LDL-cholesterol of the MI group as well as the MO was much higher than that of C. The elevated total-cholesterol level of the Mi group was due to increased LDL-cholesterol and that of the MO was due to increases in both VLDL-cholesterol and LDL-cholesterol. As the result of these differences, the atherogenic index of the MO was significantly higher than that of C. The incidence of hypercholesterolemia( 200mg/dl) of the MI and MO was 60.0% and 77.8% respectively, All of the physical parameters and indexes except height were positively correlated with plasma lipid levels, systolic blood pressure, and blood glucose concentration. The analyses of the correlated with plasma lipid levels, systolic blood pressure, and blood glucose concentration. The analyses of the correlation indicated that central fat to peripheral fat ratio and waist to thigh girth ratio seemed to be closely associated to plasma lipid levels and atherogenic index. The MO had significantly higher systolic blood pressure than C and significantly higher blood glucose concentration was found in both MI and MO than in C. These results confirmed that obesity in childhood may be relevant to chronic metabolic diseases such as abnormal lipid metabolism, atherosclerosis, high blood pressure and diabetes mellitus.