Polycystic ovarian syndrome (PCOS) is a common ailment that threatens female reproductive and endocrine function in the period of reproductive age. Major characteristic clinical features and the clinical biochemical manifestations of PCOS are high levels of androgen, continuous anovulation and polycystic ovarian change characteristics, and it is often accompanied with insulin resistance and obesity. Complex etiology and pathogenesis of PCOS are still not clear up to now, it may be associated with the roles of genetic factors and environmental factors. This paper focuses on etiology and related research progress of PCOS, in order to help medical workers get further understanding of this disease, and improve the prevention and treatment of clinical diagnosis of this disease.