Turner syndrome (TS) is the most frequent sex abnormality in females, generally associated with a 45,X0 karyotype. Although neurological complications are frequently part of the clinical picture, serious brain abnormalities are quite rare in TS. Epilepsy in TS is not frequent and so far only few cases have been reported, usually associated with cortical dysplasias. We report a Turner patient showing severe neurological impairment, refractory epilepsy and MRI finding of bilateral perisylvian hypoplasia. The possible dysgenetic role of X-chromosome on cortical morphogenesis is also discussed.