A 70 year-old woman visited our hospital complaining of macrohematuria. She had undergone augmentation ileocystoplasty for tuberculous bladder atrophy 50 years previously. CT and cystoscopy showed tumor at the ileovesical anastomosis. She underwent a partial cystectomy. The pathological diagnosis was adenocarcinoma of the ileal segment Recurrence was observed with rapid progression. The patient died 8 months after the operation. In Japanese literature, 43 cases of carcinoma arising in augumented bladder have been reported. Average period to the diagnosis of the cancer from the ileocystoplasty is 33 years. The period of our case was 50 years, the longest in 43 cases.