A pleomorphic (giant cell) carcinoma of the esophagus is reported in a 52-year-old man who had dysphagia and weakness. The 8-cm-high vegetating tumor consisted of solid sheets of poorly cohesive epithelioid cells broken into clusters by strands of stroma. Numerous giant cells showing phagocytic phenomenon were present. Immunochemical analyses demonstrated the epithelial origin of the neoplasm, although most of the tumor cells strongly expressed vimentin. Numerous tumor cells expressed synaptophysin. Neurosecretory granules were detected in some tumor cells on electron microscopic examination. The patient died 4 months after he became symptomatic. As far as we can ascertain, this is the first case report describing a pleomorphic carcinoma arising in the esophagus. This poorly differentiated carcinoma might be of neuroendocrine differentiation. In the esophagus, pleomorphic carcinoma must be distinguished from polypoid tumors such as carcinosarcoma and malignant melanoma.