Percutaneous cryoablation is a potential cure for hepatocellular carcinoma (HCC).This study reviewed retrospectively clinical data from 14 patients who underwent cryoablation of huge HCC (long diameter >7cm).The side effects of cryosurgeries and liver function reverse were recorded and compared everyday.All the patients survived cryosurgery and none died before leaving hospital 2 weeks later.Despite liver-protective treatment before cryosurgery, alanine transaminase (ALT)and aspartate transaminase (AST) levels were increased significantly, but returned to preoperative levels 2 weeks post-cryosurgery.Before cryosurgery, mean total bilirubin (T.BIL) and direct bilirubin (D.BIL) levels were normal;8-10 days after cryosurgery, they increased more than two-fold, but returned to the preoperative level 2 weeks post-cryosurgery.Serum transaminase and bilirubin levels were compared between hepatitis B positive and negative patients.The hepatitis B negative groups AST level increased significantly 1 day post-cryosurgery (mean, 186U/L) and decreased to the preoperative level at day 14.In the hepatitis B positive group, means transaminase and bilirubin reached peak values at different days post-cryosurgery.Overall, ALT and AST are valuable indicators of liver function impairment following cryosurgery.In patients with hepatitis B virus, close attention to the serum bilirubin level should be paid 8-10 days after cryosurgery.Liver-protective treatment may alleviate liver function impairment caused by cryosurgery of huge HCC.