Abstract： Objective： To observe the clinical effect of the therapy of Guizhi Fuling Pill and Erchen Decoction combined with routine western medicine on polycystic ovary syndrome(PCOS). Methods ： A total of 82 patients with PCOS were selected as the research objects and divided into the control group and the observation group according to the random number table method， with 41 cases in each group. The control group was treated with routine western medicine， and the observation group was additionally treated with Guizhi Fuling Pill and Erchen Decoction based on the treatment of the control group. The clinical effects，ovarian function，serum biochemical factors and safety were compared between the two groups. Results：The total effective rate was 87.80% in the observation group，higher than that of 68.29% in the control group(P＜0.05). Before treatment， there was no significant difference being found in the comparisons of ovarian volume，endometrial thickness and pulsatility index(PI) and resistance index(RI) of ovarian artery between the two groups(P＞0.05). After treatment，the levels of ovarian volume，PI and RI in the two groups were lower than those before treatment，the levels of endometrial thickness was higher than those before treatment(P＜0.05)； after treatment， the levels of ovarion volume， PI and RI in the observation group were lower than those in the control group， the levels of endometrial thickness was higher than the control group(P＜0.05). Before treatment，there was no significant difference being found in the comparisons of levels of serum luteinizing hormone(LH)， estradiol(E2) and Homeostatic Model Assessment of Insulin Resistance(HOMA- IR) between the two groups(P＞0.05). After treatment， the levels of serum LH，E2 and HOMA-IR in the two groups were lower than those before treatment(P＜0.05)； after treatment，the above three levels in the observation group were lower than those in the control group (P＜0.05). There was no significant difference being found in the comparison of total incidence of adverse reactions between the two groups(P＞0.05). Conclusion： The therapy of Guizhi Fuling Pill and Erchen Decoction combined with routine western medicine for PCOS can enhance the clinical effect，improve the ovarian function and levels of sex hormones，and reduce the insulin resistance，with good safety.