A 59 year-old-Japanese female was referred to our hospital for tumor-induced abdominal pain. Dynamic computed tomography (CT) demonstrated a tumor, 88×73 mm in diameter, which was adherent to the caudate lobe of the liver and pancreas. Based on these findings, we performed a laparotomy with a preoperative diagnosis of hepatocellular carcinoma (HCC) originating from the caudate lobe of the liver. The tumor could be dissected from the liver, however, it had infiltrated into the common hepatic artery, leading to incomplete extirpation of the tumor. Histological examination revealed that the tumor was an ectopic HCC. Lenvatinib mesylate (lenvatinib) was used as systemic therapy for growth of the remnant tumor 16 days after surgery. CT performed during two months after initiating lenvatinib revealed that the tumor size had reduced with a decrease in vascularity, which was deemed to be a partial response. CT performed three months after the initiation of lenvatinib demonstrated regrowth of the tumor. The patient died of HCC 164 days after surgery.