A 49-year-old man came to our department for the purpose of scrutinizing liver tumor. CA19-9 and CA125 increased, and AFP and PIVKA-Ⅱ were within the normal range. CT showed a large number of early ring enhanced tumor, and a tumor thrombus in the left branch of the portal vein. Tumor biopsy revealed adenocarcinoma. Chemotherapy(gemcitabine, cisplatin plus S-1: GCS)was performed for intrahepatic cholangiocarcinoma(r/o combined hepatocellular carcinoma and cholangiocarcinoma). Lenvatinib was administered because portal vein tumor thrombus and PIVKA-Ⅱ increased after GCS therapy. Two months later, CA19-9 and PIVKA-Ⅱ were decreased and portal vein tumor thrombus was shrunk. Extended left hepatectomy was performed for the purpose of disease control. Histopathological examination revealed some hepatocellular carcinoma components in intrahepatic cholangiocarcinoma. Tumor thrombus was vitrified and necrotic. After hepatectomy, administration of lenvatinib was continued for the residual lesion, and no significant tumor growth was observed.