We experienced a rare case of spindle cell carcinoma of the breast. A 45-year-old woman complaining of a left breast tumor with pain was admitted to our hospitaI. Radical mastectomy was performed with a preoperative diagnosis of sarcoma. However, local recurrence, as well as bilateral lung and ileal metastasis, subsequently occurred. Each was resected at the time it was found, but the patient died approximately two years and two months after the first operation. We had difficulty in making the diagnosis, because metastasis to the ileum of spindle cell carcinoma had not been reported previously. According to the Japanese literature on cases dying of this disease, distant metastasis is more frequent than local recurrence. Further-more, with recurrence, the prognosis is worse than with common breast carcinomas. Spindle cell carcinoma presents many problems regarding therapy and prognosis. Further accumulation and analysis of cases is thus necessary.