Hilar cholangiocarcinoma always presents with a mass, thickness of the bile duct wall or nodules in the bile duct. Computed tomography (CT) can demonstrate the above findings with high partial resolution as well as dilation of the intrahepatic bile duct. CT can show the field and the involvement of adjacent vessels on 3D reconstruction images for hilar cholangiocarcinoma spreading along the lumen of the bile duct. CT images can also demonstrate vessel involvement when evaluating the resectability. When combined with 3D reconstruc-tion, the sensitivity and specificity of CT imaging can reach 90.5% and 91.7% , respectively, for detecting vessel involve-ment.