To study the influence of transcatheter arterial embolization therapy (TAE) on the portal tracts, 32 cases of hepatocellular carcinoma (HCC) with a history of TAE were examined. Portal tract elements are said to be mainly supplied by hepatic arterial blood, as is HCC. The following changes were found: peribile duct fibrosis; biliary epithelial injuries; bile duct necrosis; fibrous thickening of the intima and adventitia of arteries; thrombosis or stenosis of portal vein branches; and fibrosis of portal tract itself. We failed to correlate these histopathologic changes with the frequency of TAE or the interval between TAE therapy and surgery or autopsy. Semi-quantitative assessment disclosed that vessels of the peribiliary vascular plexus (PVP) which are known to be derived from hepatic arterial branches, were considerably decreased. There was little correlation between the degree of reduction of PVP and the observed histopathologic changes of portal tracts. It is suggested that TAE causes adverse effects on the elements of portal tracts and a reduction in the PVP in the vicinity of HCC, but the relationship between them is unclear.