A five-month-old girl with optic atrophy presented porencephaly on computerized tomography of the brain. Diffuse intracranial hemorrhages occurred in the neonatal period as a result of thrombocytopenia. As the maternal platelets were negative for the platelet antigens, the diagnosis of neonatal alloimmune thrombocytopenia was made. The present case shows that optic atrophy as a single finding can lead to the diagnosis of a rare disorder.