This essay illustrates the various CT findings of the hepatic venous invasion of the hepatocellular carcinoma with an anglographic correlation. The thrombosed hepatic vein is directly visualized as a dilated tubular structure or multiple nodules of the similar attenuation to that of the parenchymal tumor, connecting the parenchymal tumor and the inferior vena cava on contrast enhanced CT scans. Enhancement of the thrombosed vein on spiral CT scans obtained in early arterial phase can suggest thrombosis caused by tumor invasion rather than a simple thrombosis. When the thrombosed hepatic vein is not directly visualized and replaced by a large tumor, the tumor thrombi within the inferior vena cava or right atrium can suggest the presence of the hepatic venous invasion.