We present a case with prenatal diagnosis of an intracranial high-flow pial arteriovenous fistula that was draining into the vein of Galen in the third trimester of pregnancy. The child was treated by transcatheter embolization with N-butyl 2-cyanoacrylate (NBCA) via the umbilical artery in the early neonatal period due to intractable cardiac failure. Hydrocephalus developed and a ventriculoperitoneal shunt was placed. At the time this report was prepared, the patient was 20 months old and without cardiac failure, but with a delay in neurological development. Prenatal diagnosis and endovascular treatment in the early neonatal period is important in preventing heart failure and resultant mortality due to such high-flow vascular malformations. To the best of our knowledge, the combination of prenatal diagnosis of an intracranial high-flow pial arteriovenous fistula draining into the vein of Galen and endovascular treatment in the early neonatal period is presented here for the first time.