The Dextrostix/Reflectance Meter (GLUCOSCOT GT-4310) for measuring blood glucose con centration was studied. We compared 75 blood glucose values measured by GLUCOSCOT with serum glucose values by laboratory glucose oxidase method. And their correlations were excellent (r=0.96961). This study proved that this portable monitor is valuable in providing anesthesiologists with a rapid and precise method for monitoring blood glucose concentrations in operating room. Perioperative blood glucose concentrations were measured by GLUCOSCOT in gynecologic patients anesthetized with Thalamonal (group 1), halothane (group 2) or enflurane (group 3). Blood glucose values increased significantly after intubation and more increased after start of surgery with time, but these changes were not significant clinically (<120 mg/dl). Changes of blood glucose, mean blood pressure and pulse rate were not different statistically from each other groups.