Therapeutic effect of percutaneous microwave coagulation therapy was evaluated in nine patients with hepatocellular carcinoma who had been given percutaneous ethanol injection therapy (PEIT) but did not show sufficient effects. Subjects were nine patients with hepatocellular carcinoma diagnosed by biopsy and the major tumor length was between 9 and 42 mm. As a treatment, PEIT was performed first in all the patients. PMCT was performed in the cases in which sufficient amount of ethanol could not be administered due to self-uncontrollable pain and marked drainage of ethanol into vascular system and in those which had residual tumors after PEIT. When effects were judged by dynamic CT or dynamic MRI, tumor necrosis effect was 100% in all the cases and, therefore, the treatment was finished. In the present study, PMCT was performed for the tumor remaining after PEIT and combination of these therapies was considered effective since the residual tumor was small and tumor necrosis effect of 100% was available relatively easily.