We report a case of Dyke-Davidoff-Masson syndrome (DDMS) in whom left vagal nerve stimulation (VNS) resulted in worthwhile seizure reduction (Engel's Classification Class III). A 20-year-old woman with DDMS whose seizures were medically intractable was successfully treated using left VNS. She was born at term by unsuccessful forceps-assisted vaginal delivery. Her seizures started at the age of 4. There was no detectable mental retardation. Her seizures were intractable although she had been receiving three medications for sixteen years. She underwent left vagal nerve stimulator placement. Pre-stimulation seizure frequency was three seizures per month. This case shows that VNS is an alternative treatment procedure for medically intractable seizures in DDMS. To our knowledge, this is the first case in the world literature reporting worthwhile seizure reduction in DDMS after VNS.