Polycystic ovarian syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age. It is characterizedhyperandrogenism, rare ovulation or anovulation, and ovarian polycystic changes. Due to the heterogeneity of clinical manifestations, the pathogenesis of PCOS has not yet been fully elucidated, but genetic factors are considered to be the main pathogenesis of PCOS. Changes in epigenetic modifications such as DNA methylation and X-chromosome inactivation patterns may affect the of androgen receptor genes and insulin genes, thereby altering androgen activity, increasing androgen levels, and ultimately leading to PCOS. Peroxisome proliferator activated receptors (PPARs) are members of the nuclear hormone receptor superfamily. Peroxisome proliferator activated receptor γ (PPARG) is the major subtype of the PPARs family in ovarian granulosa cells. PPARG plays an irreplaceable physiological function in reproduction and metabolism. It is involved in ovarian steroid metabolism, ovarian tissue remodeling, granulosa cell cycle regulation and insulin-glucose metabolism. Further research on the role of PPARG in the pathogenesis of PCOS can provide a theoretical basis for the prediction, diagnosis and treatment of long-term complications, which is reviewedthis article.