Percutaneous cryoablation is a potentially curative treatment for hepatocellular carcinoma (HCC).After liver cryosurgery, rapid elevations of transaminases and bilirubin are common, but are usually transient and normalize within a few days.This study retrospectively reviewed clinical data from 51 patients who underwent liver cryoablation in our hospital during the past 4.5 years.Sixty-six percutaneous cryoablations were performed in these patients and transaminase and bilirubin levels before and after the procedure were observed.Although most patients received liver-protective treatment before cryosurgery, transaminase levels were double (mean alanine transaminase (ALT) and aspartate transaminase (AST) were 71 U/L and 85 U/L, respectively) the normal ranges in our hospital.One day after cryosurgery, ALT and AST had increased 3.3-fold (peak mean was 241 U/L) and 5-fold (peak mean was 427 U/L), respectively, but were close to the preoperative level 5 days post-cryosurgery.No significant increase of serum bilirubin was observed.Serum transaminase and bilirubin levels were compared between hepatitis B positive and hepatitis B negative patients.Only in the hepatitis B positive group were total bilirubin (74 Imol/L/23 Imol/L =3.2) and direct bilirubin (45Imol/L/12 Imol/L =3.8) more than 3 times the preoperative level 7-9 days after treatment.Overall, ALT and AST are valuable as indicators of liver function impairment following cryosurgery.In patients with hepatitis B virus,serum bilirubin was 3 times the preoperative level 7-9days after cryosurgery.Liver-protective treatment may alleviate liver function impairment due to cryosurgery.