So-called carcinosarcoma of the esophagus is rare malignant tumors composed of carcinoma and sarcomataous components. We described a case of so-called carcinosarcoma and reviewed some literature. A 67-year-old man visited our hospital because of difficulty in swallowing, general fatigue, and sore throat. Barium swallow esophagogram showed a large polypoid lesion in the middle, lower thoracic esophagus. Endoscopy also demonstrated a pedunculated polypoid tumor. Histological examination of the biopsy specimen revealed malignant findings. Thoracic esophagectomy with cervical, thoracic, abdominal dissection was performed. A polypoid tumor, 10.5 x 5.2 x 3.5 cm in size, was removed. In the polypoid lesion, spindle-shaped cells made interlacing bundles similar to sarcoma and surrounded nests of squamous cell carcinoma. Near the pedicle, squamous cell carcinoma invaded muscularis mocosae. And lymph node metastasis was detected. Epitherial membrane antigen (EMA) was detected in some parts of the polypoid lesion. So according to Guide Lines for Clinical and Pathological Studies on Carcinoma of the Esophagus, this case was diagnosed as so called carcinosarcoma.