A 60-year-old woman presented at another hospital with a complaint of voiding difficulty. She had had left nephrectomy and bladder augmentation using the sigmoid colon for treatment of urinary tract tuberculosis 38 years ago. Left ovarian tumor was found by computed tomography and she was referred to our hospital. Another tumor which involved the uterus, bladder, and urethra was revealed by magnetic resonance imaging. An anterior pelvic exenteration was performed with preoperative diagnosis of left ovarian cancer with peritoneal dissemination. Histopathological examination revealed a clear cell adenocarcinoma of the left ovary and a sigmoid cancer arising in the augmented bladder. The sigmoid cancer arose from the anastomotic site between the bladder and sigmoid segment. This is the 34th case of neoplasms following augmentation enterocystoplasty reported in Japan.