Objective:To observe the clinical efficacy of “Yinshen Huatan Formula” and metformin in treating polycystic ovary syndrome of endomorphy type  Methods:Ninety cases were randomized into Chinese medicine group, western medicine group and combination group, with 30 cases in each group. Chinese medicine group was treated with “Yinshen Huatan Formula”; western medicine group was treated with metformin and combination group was treated with “Yinshen Huatan Formula” and metformin, with the course of 3 months. The clinical efficacy, BMI, WHR, glucose metabolism, and sex hormone levels were observed  Results:①The overall effective rate was 70.00%, 76.67% and 83.33% in the Chinese medicine group, western medicine group and combination group respectively; with significant differences among the groups(P<0.05). The clinical efficacy of the combination group was superior to that of the other two groups. ②There were significant differences in the levels of BMI, WHR between before and after treatment in the combination group(P<0.05); After treatment, the levels of BM and WHR in the combination group were lower than those of the other two groups(P<0.05). ③ There were significant differences in the levels of FINS and HOMA-IR between before and after treatment in western medicine group and combination group(P<0.05); After treatment the levels of FINS and HOMA-IR of the western medicine group and combination group were lower than that of the chinese medicine group(P<0.05). ④ There were significant differences in the levels of LH and T between before and after treatment in Chinese medicine group and combination group (P<0.05); After treatment, the levels of LH and T of the Chinese medicine group and combination group were lower than that of the western medicine group (P<0.05)  Conclusion:Combined “Yinshen Huatan Formula” and metformin can alleviate clinical symptoms and regulate endocrine condition and boost the ovulation in treating PCOS of the endomorphy type.