As a treatment for malignant ovarian tumor, whole abdominal irradiation including the upper abdomen is more useful. Between December, 1975 and November, 1980, we additionally applied whole abdominal irradiation by the moving strip technique (1,600 rad) after operation and whole pelvic irradiation (3,000 rad) to 43 cases of malignant ovarian tumor (serous cystadenocarcinoma-24, mucinous cystadenocarcinoma-7, mesodermal mixed tumor-3, clear cell carcinoma-2, endometrioid carcinoma-2, malignant granulosa cell tumor-1, malignant Brenner tumor-1 and metastatic tumor-3). Out of 10 cases with complete resection of the tumor, nine patients are surviving without recurrence, and also some advanced cases with incomplete operation have shown a remarkable reduction in the tumor size. As to complications, diarrhea during lower abdominal irradiation as well as nausea and vomiting during upper abdominal irradiation were observed, but no characteristic changes were observed upon checking peripheral blood, liver and renal function; thus most cases completed the whole therapy without interruption. Some cases that had appeared to respond favorably course showed a rapid recurrence after 1.5-2 years, so four cases were given repeated irradiation, but results were not so satisfactory. Further study of radiation and combinations with other therapies is now being tried.