In the present paper, efforts have been attempted to analyze alteration of the basal metabolism before and after gynecologic operation and to contribute to the treatment. The studies were made at the Dept. of Obstetrics and gymecology, Okayama University Medical School, on 77 cases of laparotomy. The basal metabolism was measured by Knipping's apparatus before and after the operation and the value obtained was referred to Harris-Benedict's table to determine the percentage of the basal metabolism. The summary of the results is as follows: 1. Normal value was discussed in the evaluation of 26 healthy nonpregnant woman who had not been suffered from any serious diseases. It was 11.27% 13.16≧m≧9.38 21.07≧x(0)≧1.47 2. In 77 cases before operation, it was 17.41% on the average and was significantly increased compared with the normal value. 3. In the analysis of these values, the basal metabolism of cases with fibroma uteri and carcimoma of the cervix was significantly increased compared with those of the healthy women. On the other hand, those of the cases with benign ovarian tumors had no significant increase. 4. Each value which was measured on the 5 th, 10 th and 15 th day after operation, had a close relation with that before operation. That is, in cases which had high values before operation, basal metabolism dropped after operation and in cases with low values, it was accelerated after operation. These tendency was observed in all cases. 5. As to analysis of values of each disease, cases with fibroma uteri was accelerated significantly on the 10 th day after operation as compared with those before operation and of the 5 th day after operation. In cases with benign ovarian tumors no significant difference was obtained between values after and before operation. Measurements of patients with carcinoma of the cervix were taken on the 5 th, 10 th, 15 th, and 20 th after operation and there was no significant difference each other between these values. But the average value which was measured on discharge was significantly lower than those before operation and of the 20 th day after operation. 6. As to analysis of values at the time of their discharge, a significant difference was recognized only in a case with fibroma uteri and it was significantly lower than that before operation inspite of acceleration compared with the normal value.