A retrospective analysis of survival data of 52 cases with brain astrocytomas was presented. All patients received post-perative radiotherapy in the period of 1973~1983 at YUMC, Yonsei Cancer Center. There were 24 patients with Grade II, 12 patients with Grade III and 16 patients with Grade IV astrocytomas. Survival rates were analyzed according to histologic grade of malignancy, age, tumor location. radiation dose and extent of surgical tumor resection. 5 year actuarial survival for patients with Grade II astrocytomas was 32.9% ad Grade III was 42.9%. The 1 year and 2 year survival rate of Grade IV astrocytomas were 46.7% and 0%. Histologic grade of tumor was important prognostic factor in brain astrocytomas. Age and extent of surgical resection were significant prognostic factors in all grades of astrocytomas and tumor location and radiation dose were significant in Grade II astrocytomas.