Objective To investigate the clinical effects of metformin combined ovulation therapy on women with polycystie ovary syndrome(PCOS).Methods sixty-patients with PCOS were classified into 2 groups, the test group were treat by dimethyl biguanide and clomiphene and CC-hMG/hCG, the control group only used CC-hMG/hCG, all of them were be treated one cycle.Results there were 2 case had pregnancy during taking dimethyl biguanide orally. Effective case were 27, that is 27/28, and the time and the dose of use the CC-hMG/ hCG were (3.84±0.6)days and(7.84±1.8) rami individually, only one case were inefficacious.the control group had 25 effective case, and the time and the dose of use the CC-hMG/hCG were (4.84±1.6) days and (9.34±2.7) rami individually, there were significant difference between the two groups(P<0.05).Conclusion Metformin may effectively improve insulin resistance, reduce serum androgen level, and recover ovulation function in women with PCOS. Key words: polycystic ovary syndrome; metformin; clomiphene