1. Objectvies This experimental study was designed to investigate the effect of cheongpesagan-tang extract on the obstruction of the lipase activity and weight, plasma, UCP1, 2 mRNA in db/db mouse. Material and Methods: The body weight loss, food intake, feeding efficiency ratio, weight of the internal organs (liver, kidney, epididymal fat, brown adipose tissue), plasma glucose, triglyceride, total cholesterol, white adipose tissue, adipocyte size distribution, expression of UCP1, 2 mRNA were measured in db/db mouse administered Cheongpesagan-tang extract for 6 weeks. These were then compared with those of control groups administered the diet. 2. Results 1) Inhibitory effect against lipase activity was Kilgyung(81.7%), Nabokja (73.1%), Seungma(73.0%), Daewhang (68.4%), Kalgeun (55.3%), Kobon(34.5%), Hwanggeum(4.2%). 2) In the sample group, the body weight was significantly decrease than that of control group. 3) In the sample group, the weight of epididymal fat showed significantly decrease than that of control group. 4) In the sample group, triglyceride showed significantly decrease than that of control group. 5) In the sample group, distribution of adipose tissue showed significantly larger than that of control group. 6) In the sample group, UCP1, 2 mRNA in BAT showed significantly increase than that of control group. 3. Conclusions These results show that cheongpesagan-tang has an effect on the treatment of obesity.