Adenoid cystic carcinoma of the esophagus is a rare tumor and has been considered to be counterpart of the salivery gland. The patient we experienced was a 60-year-old female who had a tumor in the lower third of the esophagus. The tumor was located in the submucosa and showed histologic features similar to those of the salivary gland. Electron micrsopic examination revealed ductal structures invested by basal lamina, and clusters of basaloid cells with tonofilaments and desmosomes. No myoepithelial cells were identified. Immunohistochemical studies for S-100 protein, cytokeratin and vimentin were performed. A few cells showed positive reaction to the S-100 protein. These findings suggest that the esophageal adenoid cystic carcinoma arises from the duct of submucosal gland.