We report a case of liver metastasis from colon cancer successfully treated with radio-frequency ablation therapy. The patient was a 75-year-old man. We performed sigmoidectomy in February 2006, but a metastatic-focus in S5 segment of the liver with the size of 28 mm was discovered by November 2006. Chemotherapy was enforced to the patient but we could not control the metastasis. There were multiple hepatic-cysts in his liver and one with size of 60 mm surrounded the metastatic-focus. RFA therapy was performed after enforcing a percutaneous ethanol sclerosing therapy to the neighboring hepatic-cyst. After 4 months from RFA therapy, the CT showed a good cauterization effect on the metastasis. We thought that RFA therapy after enforcing a percutaneous ethanol sclerosing therapy to the neighboring hepatic-cyst was as good as hepatectomy with low invasiveness.