Abstract： Objective： To explore the regulatory mechanism of Bushen Cupailuan Decoction on hypothalamus- pituitary- ovary axis through the rat model of polycystic ovary syndrome (PCOS). Methods： A total of 150 6- week old SD rats were randomly divided into blank control group (n=30) and PCOS observation group (n=120). The observation group was randomly divided into four groups： model group， positive control group， low- dose group and high- dose group， with 30 rats in each group. The blank control group was fed in the normal environment. The observation group was given intraperitoneal injection of bacterial lipopolysaccharide (LPS)，the positive control group was given Diane 35 solution，the low-dose group of Chinese medicine was given low-dose of Bushen Cupailuan decoction，and the high-dose group of Chinese medicine was given high- dose of Bushen Cupailuan decoction. The changes of ovary coefficient，uterus coefficient and estrous cycle of rats in each group were analyzed，and their serum sex hormone levels were analyzed. The protein expressions and mRNA levels of Kisspeptin and GnRH in hypothalamus of rats in each group were observed. Results：There was no significant difference between the high-dose group and the blank control group (P＞0.05). The ovarian coefficient and estrous cycle in the Chinese medicine high-dose group were lower than those in the model group，the positive control group and the Chinese medicine low-dose group (P＜0.05). The ovarian coefficient and estrous cycle of the blank control group were lower than those of the model group， the positive control group and the Chinese medicine low- dose group (P＜0.05). The levels of luteinizing hormone (LH) and testosterone (T) in the pituitary gland of the Chinese medicine high-dose group and the blank control group were lower than those of the other groups，while estradiol (E2) and progesterone (P) were higher than those of the other groups (P＜0.05). The level of E2 in Chinese medicine high-dose group was significantly higher than that in positive control group (P＜0.05). The expressions of kisspeptin protein and mRNA in hypothalamus of Chinese medicine high- dose group and blank control group were higher than those of other groups， while the protein and mRNA expressions of GnRH were lower than those of other groups (P＜0.05). Conclusion： Bushen Cupailuan Decoction can regulate ovarian function， regular hormone level， and regulate the expressions of Kisspeptin and GnRH in pituitary，reduce the sensitivity of pituitary to Kisspeptin and GnRH， and promote ovulation.