Objective To set up a rat animal model of endometriosis. Methods Lewis rats were divided into three groups: 1. The uterine tissues of Lewis rats were autotransplanted to the surface of the peritoneal cavity and the mesenteries.2. The distal or the proximal uterine tissue squares of rat uterine horn were sutured to the peritoneal cavity. 3. The same fat squares were transplanted into the peritoneal cavity,then pathological changes were observed after four or eight weeks. Results No difference was noted in the area and survival rate between implant to the peritoneal cavity and that to the mesenteries(P>0.05). Uterine distal squares that were autotransplanted to the surface of the peritoneal cavity were larger and more easy to success(P<0.05). The endometrial implants in the rats became cystic structures that were composed of endometrial gland and stroma.The macroscopic and histologic appearance was consistant with endometriosis. Conclusion The autotransplanted surgically model of endometriosis would grow stably with easy success. It could be a suitable animal model.