We report a case of lung cancer producing CA19-9 and amylase. A 58-year-old woman was admitted with dry cough and right chest pain. Chest X-ray and CT showed a mass shadow in the right lung field and right pleural effusion. Histological examination of a lung specimen obtained by TBLB and cytological examination of pleural effusion showed adenocarcinoma. The diagnosis of lung adenocarcinoma was made. CA19-9 values in serum and pleural effusion were very high. Amylase value was high in pleural effusion, but that in serum was normal. The amylase isozyme pattern was salivary-type. No abnormality was detected on abdominal CT and ultrasonography. In spite of treatment of the pleural effusion, the patient's condition gradually deteriorated and she died of respiratory failure. Histological examination of lung specimens obtained at necropsy showed moderately differentiated papillary type adenocarcinoma. Immunohistochemically, the tumor cells stained positively for both CA19-9 and amylase. We conclude that the lung cancer produced both CA19-9 and amylase.