A resected case of huge liver metastasis of hepatoid adenocarcinoma of the lung is described. A 77-year-old man who presented a solitary huge liver tumor was admitted to our hospital. He had undergone right lower lobectomy of the lung for lung cancer one year before. The view of imaging studies was not a typical one of hepatocellular carcinoma. Serum levels of AFP and PIVKA-II were 334,500ng/mL and 3,890mAU/mL, respectively, and the proportion of AFP L3 was 97.9%. It was thought that they were strongly diagnostic for hepatocellular carcinoma. Extended right lobectomy of the liver was performed. Microscopically, it was poorly differentiated adenocarcinoma and diagnosed as liver metastasis from the formerly resected lung cancer. The tumor was composed of cells with both sheet-like growth and tubule formation. The neoplastic cells, in the sheet-like growth resembled hepatocellular carcinoma cells. By immunohistochemical staining with anti-AFP and anti-PIVKA-II antibodies, cancer cells of both the primary and metastatic lesions were positive. The patient eventually died of multiple liver and bone metastasis 6 months after the operation.