We herein describe a 71-year-old female case of cholangiocarcinoma. Computed tomography of the abdomen showed an infiltrating lesion with low attenuation and a dilatation of the intrahepatic bile duct in the lateral segment of the liver. Positron emission tomography and computed tomography (PET/CT) revealed that the area of increased metabolic activity was detected in the lateral segment and regional lymph nodes. The tumor was diagnosed to be intrahepatic cholangiocarcinoma with lymph node metastasis. The patient underwent a left hepatectomy, and segment 1 and a lymph node dissection. A histopathological examination showed a well differentiated adenocarcinoma which had metastasized to the dissected lymph nodes. The histopathological findings of the involved lymph nodes were same as those of the hepatic tumor. PET/CT imaging study would be useful in preoperative staging of cholangiocarcinoma.