Forty-five pathologically proved cases of neonatal brain tumors (diagnosed in neonates within 60 days after birth) were reviewed from the neuroradiology archives dating back to 1964. CT was performed in 24 cases, MR in five, sonography in six, and angiography in seven. Two-thirds of the lesions were supratentorial. The most common histology was a tumor composed of primitive or poorly differentiated tissues: 12 teratomas and 12 primitive neuroectodermal tumors, four of which were typical medulloblastomas. In addition, there were nine astrocytomas (grades I-III); four cases of glioblastoma multiforme (astrocytoma grade IV); three choroid plexus papillomas; and single cases each of ependymoma, medulloepithelioma, germinoma, angioblastic meningioma, and ganglioglioma. The dominant CT appearance, regardless of histology, was a large heterogeneous lesion with associated hydrocephalus. Coarse calcification was a constant feature in the teratomas. Prognosis was poor overall, with the longest survival seen in choroid plexus papilloma and astrocytoma. Imaging studies are most valuable in identifying and distinguishing potentially curable lesions such as choroid plexus papillomas (variably sized intraventricular lesions with homogeneous enhancement) from rapidly fatal tumors such as teratomas (large heterogeneous lesions with coarse calcifications and associated hydrocephalus).