Objective: Carcinosarcoma of esophagus is an infrequent disease. Here, the pathologic data of larger specimeus of this disease are reviewed and analyzed for studying its clinical characteristics in order to provide support information for clinical diagnosis. Methods: To review and study the clinical data of 20 patients of esophageal carcinosarcoma. Results: Most of esophageal carcinosarcoma grew like pileus or polypus in esophagus, a few of them were infiltrating. Microscopic examination of the resected specimens indicated that the tumor is composed of sarcomatous element and carcinomatous element ( the main element ), and the surface of such tumor was covered mostly by carcinoma tissues. The result of biopsy showed that the tumor is squamous cell carcinoma. X-ray examination indicated that there was polypus-like smooth and tidy filling defect in the esophagus of such patient, and its mucous membrane showed "daubing-trace" like characteristics. Conclusion: Carcinosarcoma of esophagus is a tumor of low invasion, which grows mainly in the esophageal lumen. The clinical symptoms of this tumor are different from those of esophagus carcinoma in certain degree. The "daubing-trace" like characteristics is typical of X-ray picture. The results of most endoscopic biopsies demonstrate squamous cell carcinoma or lower differentiation carcinoma, which are difficult for confirmed diagnosis before operation.