Objective To investigate preventive effect of Huanshao capsule on postoperative re-currence of moderate to severe intrauterine adhesion and its impact on postoperative pregnancy rates.Methods A total of 163 patients with moderate to severe intrauterine adhesion after surgery were se-lected as study subjects,and randomly divided into observation group(n=82)and control group(n=81).The control group received conventional treatment,while the observation group additionally took Huanshao capsule postoperatively.Serum fibronectin(FN),laminin(LN),vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGF-β1)levels were compared between two groups at 1 month,3 and 6 months postoperatively.Endometrial thickness,uterine artery blood flow resistance index(RI),postoperative pregnancy rates and quality of life scores were also com-pared.Results At 3 and 6 months postoperatively,serum FN,LN and VEGF levels in the observa-tion group were lower than those in the control group(P＜0.05).At 6 months postoperatively,serum TGF-β1 in the observation group was lower than that in the control group,with statistically significant difference(P＜0.05).At 3 and 6 months after surgery,endometrial thickness in the observation group was significantly higher,uterine artery flow RI was significantly lower than,and scores of various quality of life(physiological function,physical pain,social function and mental health)were signifi-cantly higher than those in the control group(P＜0.05).At 6 and 9 months postoperatively,the pregnancy rate in the observation group was higher than that in the control group,with statistically sig-nificant differences(P＜0.05).Conclusion Huanshao capsule can significantly reduce serum FN,LN,VEGF and TGF-β1 levels in patients with moderate to severe intrauterine adhesion after surgery,improve the postoperative endometrial environment,and increase postoperative pregnancy rates.