CT and portographic findings of 63 patients with hepatoma, undergone hepatic angiography and superiormesenteric portography for evaluation of tumor and thrombosis of portal vein and determination of indication oftranscatheter arterial embolization for palliative treatment of hepatoma from April,85 to June, 86 in Hanyanguniversity hospital, were reviewed. The results were as follows: 1. In 36 cases, portal vein thrombosis wasdetected during portography. Nineteen of 37 cases which revealed localized hepatoma in the right lobe of the livershowed portal vein thrombosis; 9 of 11 cases of the left lobe; 8 of 14 cases which were involved in entire liverrevealed thrombosis. One case localized in the caudate 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 ofportal vein thrombosis in this type were higher than in the cases of the nodular type. 3. The portal veinthrombosis appeared as filling defects of low density in the lumen of the portal veins in CT and they did notreveal contrast enhancement. 4. CT revealed well the evidences of obstructions in the cases of portal veinthrombosis and the findings were well-corresponded to the findings of the superior mesenteric portography. 5. Fiveof the cases of the portal vein thrombosis were missed in the CT and the casuses were considered as due to partialvolume effect of enhanced portal vein with partial occlusion or arterioportal shunts. 6. Six of 13 cases withocclusion of main portal vein showed cavernous transformation and they were noted as multiple small enhancedvascularities around the porta hepatis in the CT. According to the results, we conclude that CT is a usefulmodality to detect the changes of the portal veins in the patients of the hepatoma.