Endometriosis is an enigmatic disorder, which affects women in their reproductive age. Failure of recent clinical trials on non-surgical management of endometriosis confirms the role of surgery as a viable treatment of choice. However, recurrence after surgery is common. Recurrence rate varies according to the surgeon’s skills, instrumentation, surgical techniques, and to the postoperative intervention outcome. In patients with severe endometriosis, lesions usually involve the posterior cul-de-sac, anterior rectum, one or both pelvic sidewalls, involving the ureters, the rectosigmoid, and less commonly the anterior bladder, the appendix, and the small bowel. Ureteral retroperitoneal dissection becomes mandatory in extensive endometriosis due to pelvic anatomical distortion. It also leaves the bowel intact without injuring it as the pseudo-peritoneum is lifted along with the inflamed bowel. Consequently, in the surgical practice of benign pathologies, a proper knowledge of the retroperitoneal anatomy ensures complete clearance in cases of advanced endometriosis and frozen pelvis. Here, we present a very interesting case of bladder endometriosis associated with hematuria during menstruation. Partial cystectomy is the treatment of choice for patients with bladder endometriosis in most cases. Provided surgeons are skilled and lesions require no ureteral reimplantation, operative laparoscopy is a valid alternative to laparotomy for partial cystectomy.