Percutaneous microwave coagulation therapy (PMCT) and radio frequency ablation therapy (RFA) as treatments for metastatic liver cancer were examined. PMCT or RFA was administered for 18 metastatic liver cancer lesions (primary lesion: 11 colon rectal cancer, one esophagus cancer, one thyroid cancer, one pancreatic cancer, one pheochromocytoma) in 16 patients from July 1999 to March 2002. RFA was performed 1 time for 12 minutes in principle, using a Cool-tip RF system from Radionics. Patients had a mean age of 58.8 years and the mean diameter of the neoplasms was about 22 mm. Critical complications were not seen. The rate of partial recurrence was 35.3% as of March, 2002, in an average observation period of 7.3 months. On the other hand, with the medical treatment for the hepatocellular carcinoma provided during this period, the rate of partial recurrence was 14.8%. The treatment of metastatic liver cancer by PMCT and RFA is associated with a high rate of a recurrence as compared with hepatocellular carcinoma, and needs to be examined to discover ways of adaptation and improvement of the technology.