Computed tomography and portographic findings of 63 patients with hepatoma, undergone hepatic angiography and superior mesenteric portography for evaluation of tumor and thrombosis of portal vein and determinationof indication of transcatheter arterial embolizaion for palliative treatment of hepatoma from April, 85 to June, 86 in Hanyang university hospital , were reviewed. The results were as follows : 1. In 36 cases, portal vein thrombosis was detected during portography. Nineteen of 37 cases which revealed localized hepatoma in the right lobe of the liver showed portal vein thrombosis ; 9 of 11 cases of the left lobe ; 8 of 14 cases which were involved in entire liver revealed thrombosis. One case localized in the case lobe showed no evidence of invasion to portal vein. 2. Twenty-four of 34 cases with diffuse infiltrative hepatoma revealed portal vein thrombosis and the incidence of portal veinthrombosis in this type were higher than in the cases of the nodular type. 3. T e portal vein throbosis appeared as, filling defects of low density in the lumen of the portal veins in CT and they did not reveal contrast enhancement. 4. CT revealed well the evidences of obstructions in the cases of portal vein thrombosis and the findings were well-corresponded to the findings of the superior mesenteric portography. 5. Five of the cases of the portal vein thrombosis were missed in the CT and the causes were considered as due to parial volume effect of enhanced portal vein with partial occlusion or arterioportal shunts. 6. Six of 13 cases with occlusion of main portal vein showed cavernous transformation and they were noted as multiple small enhanced vascularities around the porta hepatis in the CT. According to results, we conclude that CT is a usuful modality to detect the changes of the portal veins in the patients of the hepatoma.