We report herein the case of a 79-year-old man with adenoid cystic carcinoma (ACC) of the esophagus. The tumor had a polypoid appearance and was covered by thin esophageal mucosa. As the biopsy specimens suggested a diagnosis of poorly differentiated adenocarcinoma, the patient underwent subtotal esophagectomy with reconstruction of the gastric tube via the posterior mediastinum. Histologically, the carcinoma contained basaloid cells, cribriform foci, and a certain amount of eosinophilic hyaline substance. Some of the basaloid cells were stained immunohistochemically for keratin, muscle actin, and S-100 protein, a pattern which was identical to the pattern of immunoreactivity of the myoepithelium. We reviewed 36 other cases of ACC of the esophagus reported in Japan, with special reference to the criteria for histological diagnosis.