Severe infant epilepsy is included within difficult etiologic diagnosis. Gray matter heterotopias are an uncommon cause. The authors report four observations of gray matter heteropias concerning three-, six-, seven- and nine-year-old girls, presenting no particular antecedents. No consanguinity was noted. The first occurrence of epilepsy ranged from the age of nine months to the age of four years. A mild mental retardation was found in three cases, and mental regression in one case. A status epilepticus was noted in three children. Magnetic resonance imaging scans showed subependymal heterotopias in one case and diffuse cortical heterotopias in three cases associated to a partial agenesis of corpus calloseum in one case and pachygyria in two cases.