Porencephaly is a rare congenital anomaly characterized by a cavitary hole extending from the cerebral mantle to the ventricle of the brain and covered by leptomeningeal membrane. It is now generally believed that the porencephaly respresents a fetal or neonatal destructive process of the neural tissue. Authors experienced an autopsy case of bilateral porencephaly in a 35 day old Korean male infant who died of pneumonia. The brain weighed 227 gms and morphologically well formed except for two large symmetric defects at the fronto-pariental region. These defects were characterized by cleft-like shape, covering the entire cerebral mantle with resultant direct communication bytween ventricular cavity and leptomeninges. Thin leptomeningeal trabeculae were covering the cavity. There was a smooth transition between ependyma and roof of the defects. No evidence of inflammation or circulatory disturbance was present in the brain. The remaining central nervous system was unremarkable.