The purpose of this study was to analyze the effects of long term rope-jumpinng evercise on body composition, circulation system and serum lipids level in obese elementary students. Twenty students were studied: experimental group(n=10), control group(n=10). Aged range was twelve. They underwent bicycle ergometer exercise. Body composition test was abalyzer to % Fat, FMW, LBW by biodynamic 310. Heart rate (HR), systolic blood pressure (SBP), MVO2, VO2max were measured at test and every two minutes during exercise. MVO2 was calcuated by the product of HR and SBP. Blood samples were obtained at pre(OW), mid(4W), post(8W) and were analyzing serum lipids(T.C, T.G, HDL-Cm LDL-C). This data was analyzed by two-way ANOVA betwwen each group and precritive duration. The conclusion of the study was as follows: 1. The change of weight, % Fat, FBW and LBW in each group showed the significant decrease and increase during rope-jumping exercise. Variables among each group showed not significant level. 2. the change of HR, VO2max during rope-jumping exercise in each group showed the significant decrease and increase. Changes of SBP and MVO2 in each group not showed the significant differents during rope-jumping exercise. Variables among each group showed not significant leve. 3. The change of TC, TG, HDL-C and LDL-C in each group showed the significant decrease and increase during rope-jumping exercise. Variables among each group showed not significant level.