A 64-year-old male, who had been diagnosed as having hepatocellular carcinoma, was admitted to hospital and underwent transcatheter arterial infusion therapy. CT and US examinations revealed a large tumor with air in its center. Barium meal examination of the duodenum showed a large filling defect with a central excavation. At endoscopic examination, a dark reddish tumor was seen protruding into the duodenal lumen. A biopsy specimen from this tumor revealed a hepatocellular carcinoma. The patient subsequently died of hepatic coma following gastrointestinal bleeding. An autopsy revealed that metastatic lymph nodes had infiltrated into the adjacent duodenum. Nine previous cases of duodenal metastasis from a hepatocellular carcinoma have been reported in the Japanese literature.