Abstract： Objective： To observe the effect of Cangfu Daotan tang combined with ethinyl estradiol cyproterone tablets for obese polycystic ovary syndrome(PCOS) and its effect on obese degree， glucose and lipid metabolism and hormone levels in ovary. Methods： A total of 119 cases of patients with obese PCOS were selected as the study subjects，and divided into the control group and the observation group according to the random number table method， with 59 and 60 cases in each group respectively. The control group was treated with metformin combined with ethinyl estradiol cyproterone tablets， and the observation group was treated with Cangfu Daotan tang combined with ethinyl estradiol cyproterone tablets. The clinical effects，obese degree，glucose metabolism levels，blood lipid levels，hormone levels in ovary and adverse reactions in the two groups were compared. Results：The total effective rate was 96.67% in the observation group， higher than that of 79.66% in the control group(P＜0.05). After treatment， the fasting insulin， fasting blood glucose， body mass index(BMI)， waist circumference， triglyceride(TG)， low- density lipoprotein cholesterol(LDL- C) and total cholesterol(TC) in the two groups were decreased when compared with those before treatment(P＜0.05)， and the fasting insulin， fasting blood glucose， BMI， waist circumference， TG， LDL- C and TC in the observation group were lower than those in the control group(P＜0.05)；the levels of high-density lipoprotein cholesterol(HDL-C) in the two groups were increased when compared with those before treatment，and the HDL-C level in the observation group was higher than that in the control group(P＜0.05). After treatment，the levels of luteinizing hormone(LH)/follicle stimulating hormone(FSH)， and testosterone(T) in the two groups were decreased when compared with those before treatment(P＜0.05)，and the levels of LH/FSH and T in the observation group were lower than those in the control group(P＜0.05). The incidence of adverse reactions was 1.67% in the observation group， lower than that of 20.34% in the control group(P＜0.05). Conclusion： Cangfu Daotan tang combined with ethinyl estradiol cyproterone tablets for obese PCOS has a definite curative effect，and can regulate the levels of sex hormones，decrease obese degree，and improve metabolism levels of glucose and lipid，with few adverse reactions.