A case of leiomyosarcoma of the urinary bladder in a 33-year-old female is reported. She was admitted with the complaint of gross hematuria. Cystoscopic examination showed a thumb-tip sized mass, located at the dome. CT showed a wide-based tumor at the dome (CT number was 60.2 H.U.). Segmental resection of bladder was performed, followed by radiation and chemotherapy (VCR, ACT-D, CPM and ADM). She is alive without evidence of disease 13 months after surgery. A case report and review of the literature are presented.