Six patients with congenital giant or multiple melanocytic nevi are studied retrospectively. The clinical, electroencephalographic and neuro-imaging findings for the four patients with neurocutaneous melanosis are described. The other two patients had only cutaneous melanosis. Three of the four with neurocutaneous alterations suffered seizures with flexion spasms and one had partial seizures. The seizures were treated and brought under control in three cases, whereas in the fourth untreated patient, only a single seizure was seen. Three patients have developed with lower intelligence levels and attention deficit syndrome. The other, whose intelligence is normal, suffers mild left hemiparesis secondary to porencephaly. None has developed hydrocephalus or symptoms of intracranial hypertension at the stages of follow-up reported, with ages ranging from 5 and 12 years. Contrary to previous reports, we found that the survival prognosis for patients with neurological involvement is favorable after a minimum follow-up of 5 years.