Polymicrogyria (involving or not the sylvian scissure) with cerebellar cortical dysplasia or vermis hypoplasia has been reported in few cases. In addition, the association between ectopic neurohypophysis and other cortical malformations, including bilateral perisylvian polymicrogyria, has been documented. We describe a girl affected by focal epilepsy since the age of 2 years. Magnetic resonance imaging (MRI) at 11 and 22 years of age showed bilateral perisylvian polymicrogyria, dysplasia of the left cerebellar hemisphere, and ectopic neurohypophysis. Genetic tests, including fluorescent in situ hybridization 22q11.2 and array-comparative genomic hybridization, and pituitary hormones (at the age of 20 years) were normal. The patient is now 22 years old, and she is seizure free under therapy with lamotrigine and levetiracetam. To the best of our knowledge, this is the first description of this complex cerebral malformation. This finding confirms that bilateral perisylvian polymicrogyria can be associated with other cerebral malformations; cerebellum and neurohypophysis must be carefully evaluated in patients with polymicrogyria.