In the present case, a primary frontal-lobe germinoma in a 20-year-old man is reported. This is the first such case to be investigated by autopsy. The tumor appeared on a CT scan as a large cystic lesion in the frontal-lobe white matter. At autopsy, the typical two-cell histology pattern was seen mainly in the area of the cyst wall. Although cyst formation is a frequent feature of germinomas, the presence of a large cystic lesion in the cerebral white matter, as demonstrated in the present case, is very rare. The present case provides further radiographic data that might be useful for the future diagnosis of this tumor, which is radiosensitive and potentially curable.