Recent years, we experienced various treatment procedures for hepatocellular carcinoma (HCC), including hepatic resection, transcatheter hepatic artery embolization and percutaneous ethanol injection. However, Some patients could not receive these treatments because of the liver dysfunction and the location of the tumors. In such cases, we have developed the microwave coagulation therapy (MCT) for HCC. From June 1992, 53 patients have received MCT : 8 cases received laparoscopic-MCT (L-MCT), 19 cases received open-MCT (O-MCT) and 26 cases received percutaneous-MCT (P-MCT). Liver function of L, O-MCT patients was worse than that of patients who received partial resection of the liver. The actual and disease-free 3-years survival rate were identical between the patients who received L, O-MCT and those who had partial hepatectomy. Out of 13 cases with tumor size greater than 2 cm in diameter receiving P-MCT, 7 cases should remaining enhanced area by a follow up dynamic CT, although none of 13 cases with tumor size less than 2 cm in diameter should enhancement. MCT is a possible choice of treatment for some HCCs.