BACKGROUND: There are many factors which cause postoperative hepatic dysfunction. Anesthetic agents are not the most common factor and there aremany other factors such as preoperative condition of the patients, site and duration of the operation, operation per se and so on. The purposeof this study is to evaluate postoperative liver function with respect to different types of surgery. METHOD: Fourty three patients were classified into three groups; 11 patients for tympanoplasty with mastoidectomy (Group 1), 16 patients for total abdominal hysterectomy (Group 2), 15 patients for subtotal gastrectomy (Group 3). All patients were anesthesized with about 2 vol% of enflurane combined with 50% nitrous oxide. Serum glutamic oxalacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and alkaline phosphatase (ALP) were measured before anesthesia, 1, 3 and 7 days after surgery in all group, respectively. RESULT: In Group 1 and 2, postoperative SGOT and SGPT levels were maintained with preoperative level during the 7days, but in Group 3, those levels were increased in the 1st day but below upper limit (p<0.05) and decreased thereafter. Alkaline phosphatase level was maintained within the normal range for all the group during the 7 days. CONCLUSION: We consider that postoperative liver functioin may be influenced by different types of surgery, and also may be influenced by anesthetic time.