To explore the effect of puerarin injection for treating infertility women with polycystic ovary syndrome（PCOS) on their sex hormone levels, insulin resistance, and antioxidant capacity. Methods: 84 infertility women with PCOS were selected as the research objects, and were randomly divided into study group and control group(42 cases in each group) by a simple random number table method between January 2019 and January 2021. The women in the control group were treated with ethinylestrone and cyproterone combined with metformin, and the women in the study group were treated with puerarin injection on the basis of the treatment in the control group. The differences of the levels of sex hormones, insulin resistance, and antioxidant capacity of women before and after three courses of treatment, and the adverse reactions situation of the women were compared between the two groups. Results: After treatment, the levels of serum luteinizing hormone, testosterone, fasting blood glucose, and fasting insulin, and the insulin resistance index value of the women in both groups had decreased significantly, and which of the women in the study group were significantly lower than those of the women in the control group. The levels of serum follicle stimulating hormone and estradiol, superoxide dismutase, reduced glutathione, vitamin C, and vitamin E, and the total antioxidant capacity of the women in both groups had increased significantly, and which of the women in the study group were significantly higher than those of the women in the control group(P<0.05). There was no significant difference in the incidence of adverse reactions(7.1% vs. 11.9%) of the women between the two groups(P>0.05). Conclusion: Adjuvant therapy of puerarin injection for infertility women with PCOS can improve their level of sex hormones, reduce their insulin resistance, and improve their antioxidant capacity.