(1.Hebei Key Laboratory of Integrative Medicine on Liver-Kidney Patterns, Institute of Integrative Medicine, Hebei university of Chinese Medicine ,Shijiazhuang, Hebei 050091；2.Hebei Collaborative Innovation Center of Integrated Traditional and Western Medicine on Reproductive Disease,Shijiazhuang, Hebei 050091):Objective:To explore the mechanism of the Bushen Wenyang Huayu Formula in regulating the Notch1/Twist1 signaling pathway-mediated epithelial-mesenchymal transition (EMT) in the treatment of endometriosis (EMs).Methods:After modeling, the weight,volume and adhesion degree of ectopic lesions were observed; the levels of sex hormones in serum were determined by ELISA;the expressions of E-cadherin, N-cadherin, Vimentin,Notch1 and Twist1 proteins were detected by immunohistochemistry and Western blot; the expressions of E-cadherin,N-cadherin, Vimentin, Notch1 and Twist1 were detected by Real-Time PCR. Results:Compared with the sham operation group,the levels of E₂, P, FSH and LH in the serum of the model group were significantly increased(P<0.05),and the levels of N-cadherin, Vimentin, Notch1 and Twist1 proteins and mRNAs in the uterine tissue were significantly increased(P<0.01,P<0.05),while the levels of E-cadherin protein and mRNA were significantly decreased(P<0.01).Compared with the model group, the volume of ectopic lesions in the high and low dose groups of traditional Chinese medicine and the western medicine group was significantly reduced(P<0.05,P<0.01),the levels of E_2, P, FSH and LH were significantly increased(P<0.05),and the levels of N-cadherin, Vimentin, Notch1 and Twist1 proteins and mRNAs in the uterine and ectopic lesion tissues were significantly decreased(P<0.01,P<0.05), while the levels of E-cadherin protein and mRNA were significantly increased(P<0.01). Conclusion: The Bushen Wenyang Huayu Formula can significantly inhibit the progression of EMs, and its mechanism may be related to the down-regulation of the expression of the Notch1/Twist1 signaling pathway, thereby regulating the EMT process of EMs.