Abstract: Polycystic ovary syndrome（PCOS），a common endocrinal disorder in women of reproductive age, causes the non-ovulation infertility. It is difficult to reach the consensus on the diagnostic criteria due to the high heterogeneity of clinical presentation and biochemical criterion in PCOS patients. At present，the common international criteria include NIH criteria，Rotterdam criteria and AES criteria. The expert consensus of China and the clinical practice guideline of AACE were also published. It is urgent to develop a diagnostic criterion of PCOS based on Chinese features. The accurate pathogenesis of PCOS is still unclear，which is related to genetic，environment，psychology，and/or combined factors. Based on characteristics of patients, therapy for those women with fertility requirement should be individual，including mainly the adjustment of life style，oral contraceptives，insulin sensitizing agents，ovulation treatment，assisted reproductive technology and operation. Meanwhile，the long-term management should be emphasized to avoid the long-term complications. In this article，the advance in diagnosis，pathogenesis and treatment of PCOS was discussed.

Key words: Polycystic ovary syndrome, Diagnosis, Therapy