From September 1970 to May 1977, the writers chose 25 cases who were treated with radiation treatment by Cobalt-60 teletherapy and Linear accelerator from those who had been histopathologically confirmed cases after their operations of malignant ovarian tumors; we analyzed their age distribution, histopathological findings, clinical staging, treatment technique, and complications during & after radiation therapy. In addition to this we also analyzed another 10 cases who could be followed up from October 1977. The results we obtained are as following and we report them with literature review. 1) The age distribution were as following : out of 25 patients seven (28%) were at their twenties, six (24%) thirties, five (20%) forties, five (20%) forties. This shows the liability to the disease of persons before forty. The cause, we think, is perhaps the superflous dyserminoma. 2) In clinical staging, out of 25 cases stage III were seven (28%), stage I & II were five (20%) respectivel . 3) When we compared the age distribution and histopathological findings, we could find out that papillary serous cystadenocarcinoma mainly appeared from forty to fifty, mucinous cystadenocarcinoma at thirties, and dysgerminoma at twenties. 4) Histopathologically papillary serous cystadenocarcinoma were seven (28%) out of 25 cases, dysgerminoma and mucinous cystadenocarcinoma were six (24%) and five (20%) respectively. 5) Main symptoms and chief complaints before treatment were abdominal distension, palpable abdominal mass and abdominal pain. 6) Among the side effects during & after the treatment gastrointestinal trouble was the most frequent one and in it diarrhea was the highest. 7) When we compared the radiation side effect according to treated techniques, Moving-strip technique showed relatively less side effect during the treatment but after the treatment each technique showed no great difference. 8) Hematologic findings during the treatment showed no difference in Hgb level bu in WBC count and platelet count showed a decreasing tendency, 21 cases out of 25 (84%) & 18 (72%) respectively. 9) When we compared the hematologic findings with each treated technique, WBC count in Moving-strip technique showed less decrease but platelet count showed no great difference. 10) Follow-up were able only in 10 cases out of 25 (40%) and 2 cases among these were dead after one and eight months respectively. 12 months survival rate was two out of five (40%) in stageI, and one out of four (25%) in stageII, which showed decreasing survival rate as the stage stageI, and one out of four (25%) in stageII, which showed decreasing survival rate as the stage progressed. Among the histopathlogical findings, the highest 12 months survival rate was 3 cases of dysgerminoma out of six (50%), and the next was one case of mucinous cystadenocarcinoma out of five (20%), and the third was one case of papillary serous cystadenocarcinoma out of seven (14.3%).