In order to select the best treatment for the patients with small hepatocellular carcinoma (HCC), histopathological progression of the small HCC (less than 3cm in diameter and within 3 lesions) was examined on 49 patients (56 nodules) who underwent hepatectomy. These 56 nodules were classified by the tumor diameters (less than 15mm, 12 nodules ; 16-20mm, 20 ; 21-25mm, 16; and 26-30mm, 8). Since extracapsular progression (extracapsular invasion, intrahepatic metastasis, or invasion to the blood vessels) was noted in only one nodule (8.3%) in HCC of less than 15mm in diameter. Percutaneous ethanol injection therapy (PEIT) seemed to be the first choice of the treatment. However, moderately or poorly differentiated HCC, or no formation of HCC capsular was observed in six nodules (50%), or five nodules (41.7%), respectively. This results seemed to be a risk factor which might cause the local recurrence after PEIT. In HCC over 16mm in diameter, capsular invasion and extracapsular progression within lcm from the tumor edge were observed in high rates (59.1% and 45.5%, respectively). Moreover, one nodule (22mm in diameter) in four nodules of resected HCC after PEIT showed the viable cancer cells of intrahepatic metastasis pathologically. In HCC over 16mm in diameter, the therapy which insure the local control including the tumor circumference such as hepatectomy or microwave coagulation therapy, should be selected.