PURPOSE: Intracranial germinoma is the most radiocurable tumor of the primary intracranial neoplasm. But, the optimum radiation dose and target volume remain controversial. In this retrospective study, we analysed the spreading pattern at presentation and the pattern of the failure and survival of intracranial germinoma. MATERIALS AND METHODS: From 1989 to 1996, 23 patients were treated for intracranial germinoma at Department of Radiation Oncology. Twenty-one patients were treated at their initial presentation and 2 patients were treated for recurrent disease. Six patients had multiple tumor masses on MRI and 7 patients had ventricular seeding on MRI. The examination of cerebrospinal fluid cytology was done in 15 patients and 3 out of 15 patients had positive cerebrospinal cytology. In tumor marker study of alpha-FP and beta-hCG, 6 patients had mildly elevated beta-hCG in serum or cerebrospinal fluid. Twenty-one patients were treated with whole craniospinal axis irradiation and 2 patients were given whole ventricular radiation therapy. The total dose was ranged between 4500cGy and 5600cGy to primary tumor site (median 5580 cGy). Dose to the entire ventricular system ranged from 1980cGy to 3960 cGy (median 2700cGy) and dose to the spinal axis ranged from 2160cGy to 3900cGy (median 2700cGy). RESULTS: Of 23 patients, 21 patients are alive without evidence of disease for median 4 years follow-up. One patient who had markedly elevated alpha-FP and beta-hCG suffered from persistent disease after radiation therapy and received 2 cycles of chemotherapy. She died 9 months after chemotherapy. One patient who developed ventricular seeding after gamma-knife was treated with whole craniospinal irradiation, he died after 1 year due to probably brain necrosis. The hematologic toxicity of 3 or 4 grade were seen in 7 patients, and patient's endocrinologic dysfunction was not deteriorated after radiation therapy. One patient had been treated with growth hormone replacement due to short stature. CONCLUSIONS: This retrospective study has confirmed the excellent result of radiation therapy in intracranial germinoma. The complication rate during or after radiation therapy is considered within acceptable range. It is necessary to further investigate the optimal dose and treatment volume of radiation therapy. The role of chemotherapy in the treatment of intracranial germinoma should be further investigated.