Using high-fat-fed C57BL/6 mice, therapeutic effects of oral administration of aqueous extracts of Platycodon grandiflorum and Acanthopanax senticosus on obesity were evaluated by comparing body and liver weights, feed intake, adipose tissue mass, blood lipid profile, and triglyceride and total cholesterol levels in liver and feces. Obesity was successfully induced in high-fat diet group. P. grandiflorum and A. senticosus were effective in reducing food intake, serum lipid levels, adipose tissue accumulation, and weight. P. grandiflorum extract reduced triglyceride and cholesterol levels in liver by excluding them in feces. A. senticosus extract increased triglyceride level in liver but decreased in feces, and decreased total cholesterol in liver and feces, indicating active ingredient of A. senticosus exert antiobesity effect through mechanism different from that of P. grandiflorum extract. These results suggest aqueous extracts of P. grandiflorum and A. senticosus have synergistic effect for prevention of hyperglyceridemia and obesity.