The clinical trial was designed to investigate the safety and effects of Bofu-tsusho-san extracts on the change of the weight, body compositions, serum in obese patients. Methods This study was a 4-weeks, double blind, comparative clinical trial. Eligible subjects had a body mass index(BMI) greater than 25 kg/m² and waist circumference(WC) longer than 85 cm in woman or 90 cm in man. Among 38 subjects, 36 subjects were randomized either to Bofu-tsusho-san or placebo. After 4 weeks of treatment, we measured anthropometric factors(weight, height, WC, BMI etc.), abdominal fat area by CT scanning, serum lipid(total cholesterol(TC), triglyceride(TG), HDL cholesterol, LDL cholesterol), blood level of variety(glucose, adiponectine, leptin, C-reactive protein(CRP) etc.), blood pressure(BP). Adverse events also evaluated. Results BMI, BP, TG, CRP were reduced and weight, WC, score of KOQOL(Korean version of obesity-related QOL scale), SRI(Stress response inventory) were significant changed in Bofu-tsusho-san. But there were no considerable difference between Bofu-tsusho-san and placebo. there were no serious adverse events in either group. Conclusion There were limitations in this study that it conducted within a short period of 4 weeks. but its weight and WC loss effect was significant and it had few adverse events.