This preliminary study was intended to clarify the effect of intraoperative fluid therapy on Acid-Base balance of the use of Hartmann's solution and 5% Dextrose solution. The arterial carbon dioxide partial pressure and oxygen partial pressure and pH are basic indices of the adequacy of ventilation in anesthetized patients, respiratory care and intensive care. In order to achieve this goal, the data collections were done at the Department of Anesthesia in Hanil Hospital from Mar., 1980 to Aug., 1980. The samplings, 20 cases, were included A.S.A. class I and II. We used 1,500 to 1,800cc/2hrs. of Hartmann's solution and 1,000cc/2hrs, of 5% Dextrose solution each 10 patients through the operative period. Observations were made for the followings; pH, PaCO₂HCO-₃. From the results of this study, there were no significant relationship between the use of 5% Dextrose solution and Hartmann's solution on Acid-Base balance during the intraoperative period.