A retrospective analysis of survival data of i2 cases with brain astrocytomas was presented. All patients received post·operative 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 o ere analyzed according to histologic grade of malignancy, age, tumor location, radiation dose and extent of surgical tumor resection. 5year actuarial survival for patients with Grade II astrocytomas was $32.9\%$ and Grade III was $42.9\%$. The 1 year and 2 year survival rate of Grade 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 (actors in all grades of astrocytomas and tumor location and radiation dose were significant in Grade f astrocytomas.