The efficacy of percutaneous cryosurgery (PCS) as a treatment strategy for unresected liver tumor was evaluated in two cases. The first patient was a 64-year-old man who was found to have multiple liver tumors after undergoing gastrectomy for gastric cancer (T3, N0, M0, Stage II). Two PCS treatments under local anesthesia decreased the size of both the treated and untreated tumors. The second patient was a 61-year-old man in whom multiple liver tumors were discovered after hepatectomy for metastases of a duodenal gastrointestinal stromal tumor, which also had been treated surgically. A third surgery was performed for mass reduction. The patient showed stable improvement after surgery, and PCS combined with administration of polysaccharide-Kureha was selected to treat the unresectable tumors. PCS was performed once a week with an overnight hospital stay. After nine PCS treatment, the remarkable reduction in the size and number of liver tumors was observed, even among non-treated tumors. The patient remains in good condition without tumors 21 months after treatment.