This study presents a patient with epileptic negative myoclonus who showed interictal focal epileptic discharges in the centrotemporal region. The patient's seizures were exacerbated by carbamazepine, zonisamide, and valproate, but completely controlled by ethosuximide, and were suggested to have some relation with thalamocortical oscillation mechanisms. Ethosuximide is supposed to be a drug of worth to try to use in epileptic negative myoclonus patients with centrotemporal spike foci.