There have been only a few reports of bronchorrhea in patients with metastatic pulmonary carcinoma. We report a case of suspected lung metastasis of pancreatic carcinoma with bronchorrhea, which was radiologically similar to bronchioloalveolar carcinoma. A 67-year-old man who had previously undergone surgical resection of pancreatic carcinoma was admitted because of a progressive cough producing copious amounts of serous sputum. A chest radiograph on admission revealed an infiltrative shadow with air bronchograms and ground glass opacities in the left middle and lower lung fields. A chest CT scan revealed a consolidative shadow with air bronchograms and bubble-like lucencies similar to bronchioloalveolar carcinoma in the left lower lobe. The histopathological features of the specimen obtained by transbronchial biopsy revealed adenocarcinoma with a pattern identical to that of the pancreatic carcinoma. Immunohistochemical staining with anti-SP-A antibody was entirely negative but those with anti-CA 19-9, Dupan 2 and CA 50 were positive in both lung and pancreatic tumors. These results strongly suggest that the pulmonary carcinoma was a metastasis of cystic adenocarcinoma of the pancreas. In summary, for a definitive diagnosis of bronchioloalveolar carcinoma, extrapulmonary adenocarcinoma as a primary site should first be ruled out.