Background: Septo-Optic Dysplasia is a rare disorder with developmental malformations that was first reported by De Morsier.SOD associated with refractory epilepsy has not been well studied. We report six cases with SOD in patients with malformation of cortical development(MCD) and medically refractory epilepsy that underwent video-EEG telemetry. Methods: Six cases of SOD plus were admitted to the Epilepsy Monitoring Unit at London Health Sciences Centre because of medically refractory epilepsy. Functional hemispherectomy in one patient resulted in significant reduction of her seizures while insertion of a vagus nerve stimulator was not successful in controlling seizures in another patient. Right temporal resection for one patient resulted in about 60% reduction in her seizures. The remaining three patients were not surgical candidates and they remained on antiepileptic drugs. Results: MCD was present in 4/6 patients. Bilateral optic nerve hypoplasia was found in 50% of the patients. EEG was abnormal in all cases(6/6).Intractable epilepsy was found in 6/6 patients. Conclusions: SOD plus was associated with medically refractory epilepsy.