Recently halothane and enflurane are commonly used inhalational anesthetic agents in our country. However, it is a controversial matter whether these agents are a potential threat to the liver. Therefore, in order to evaluate the effects of halothane and enflurane on the hepatic function, we divided a anesthetized patients into the following 4 groups. 1st group; low spinal anesthesia. 2nd group; single inhalational anesthesia with halothane.3rd group; repeated secondary inhalational anesthesia with halothane. 4th group; secondary inhalational anesthesia with enflurane following halothane. On postoperative 1st, 3rd, 5th, 7th, 10th day, we checked the levels of SGOT, SGPT and ALP. The results are as follows. group 1. Low spinal anesthesia(10 cases) ;SGOT and SGPT levels-no change or recovered in 9 cases (90%) ALP level-no change in all cases. group 2. Single inhalational anesthesia with halothane (14 cases) ;SGOT and SGPT levels-no change or recovered in 13 cases(92%) severely changed in 1 case. ALP level-no change or recovered in 13 cases (92%) group 3. Repeat 2ndary halothane anesthesia following previous halothane anesthesia. (14cases) ; SGOT level-no-change or recovered in 11 cases (79%), severely changed in 2 cases. SGPT level-no-change or recovered in 11 cases (79%), severely changed in 3 cases. ALP level-no-change or recovered in 11 cases (79%), severely changed in 1 case group 4. Repeated 2ndary enflurane anesthesia following previous halothane anesthesia. (11 cases) ; SGOT level-no-change or recovered in 8 cases (72%), severely changed in 2 cases SGPT level-no-change or recovered in 8 cases (63%), severely changed in 2 cases ALP level-no-change or recovered in 5 cases (45%), severely changed in 1 case From the above results, more cases of elevated SGOT, SGPT and ALP levels and slower recovery rate were noted in the repeated anesthesia group than in the one time anesthesia group. Not only the anesthetics themselves but also other variables such as disease severity coincidental illness, transfusion, duration of operation and so on are probably responsible for these alterations.