Authors performed angio-CT(portal &/or arterial CT) in 35 patients with various hepatic masses. We obtained portal CT in 32 and arterial CT in 13 patients. the contrast material was injected into superior mesenteric artery for portal CT and into hepatic artery for arterial CT after transfemoral cathetrization of these arteries. We concluded that portal CT was superior to other imaging modalities highly sensitive in detecting hepatic masses, especially, early hepatocellular carcinoma, daughter nodules, and subclinical metastatic hepatic malignancy, With this method, detection rate of early hepatocelluar carcinomas improved 62% in numver of patients and 90% in number of masses. Detection rate of subclinical hepatic metastases improve 60% each in number of patients and in number of masses. It was also useful for the detection of portal vein invasion. Arterial CT was useful in differential diagnosis of masses and in defining the characteristics of entire or part of the masses beca se this method revealed hemodynamic patterns more definitely.