Abstract： Objective To study the effect of high-dose mifepristone on the expression of hypoxia-inducible factor 1,(HIF-1α) and vascular endothelial growth factor(VEGF) in the endometrial tissue and research the molecular mechanisms of mifepristone in treat ment of endometrial cancer.Methods 30 patients with endometrial cancer who were treated were asked to oral mifepristone 100mg/d,the specimens from a biopsy or curettage were taken as the group before treatment,the specimens from surgery were as the group of after treatment.Another 10 cases of normal endometrium were selected as the control group.The expression of HIF-1α and VEGF were examined with immunohistochemistry.Results The expression of HIF-1 α and VEGF(78.6 ± 3.5,92.4 ± 5.1 ) in endometrial cancer was significantly higher than normal endometrium( 192.3 ± 4.7,178.4 ± 3.3,P ＜ 0.01 ),large doses of mifepristone can significantly reduce the expression of HIF-1 α and VEGF in endometrial cancer issues ( 103.2 ± 4.1,118.3 ± 4.9,P ＜0.05).Conclusion One of the molecular mechanisms of mifepristone inhibits the endometrial cancer was reduced HIF-1α and VEGF expression.