A 49-year-old female visited to our department with complaints of gross hematuria and micturition pain. Cystoscopic examination revealed a 5-cm diameter solid broad-based tumor located at the front wall of the bladder. Histologically, the tumor was composed of grade 2 urothelial carcinoma (UC) element and sarcomatous spindle cell element. Immunohistochemical examination demonstrated that both UC and spindle cells were positive for cytokeratin. In addition, spindle cells did not stain for S-100 protein or smooth muscle actin. We diagnosed the tumor as sarcomatoid carcinoma and performed total cystectomy and ileal conduit without chemotherapy and radiation. The patient has remained without any evidence of recurrence for 14 months after operation. Sarcomatoid carcinoma of the bladder has aggressive malignant potential and poor prognosis. An appropriate adjuvant therapy for sarcomatoid carcinoma with metastasis has not been established. Total cystectomy is recommended as soon as possible after pathological diagnosis in the same manner as conventional high grade UC.