Primary carcinoma of the cystic duct is a very rare condition that is diagnosed on the basis of the following criteria: (1) growth restricted to the cystic duct; (2) no neoplastic tissue in gallbladder, hepatic or common bile duct; and (3) presence of carcinoma cellls confirmed by histological examination of the growth. We report a case of primary caricnoma of the cystic duct that conforms to previously established criteria.