An 11-year-old boy, who had no remarkable past history, exhibited disorientation and abnormal behavior lasting for several hours. Continuous ictal discharges on his EEG lead to the diagnosis of nonconvulsive status epilepticus (NCSE). The administration of diazepam instantly resulted in the cessation of ictal discharges, associated with clinical recovery. Interictal spikes distributed in frontal lobes are sporadically seen, suggesting frontal lobe as an epileptic focus. After starting medication, he showed excellent clinical course without recurrence of seizure or neurological sequelae. Although NCSE is generally suggestive of poor prognosis, some subtypes of NCSE, such as partial status epilepticus and absence status epilepticus, are not always associated with adverse outcome. The present case suggests that epileptic patients who present NCSE at onset and lack interictal neurological impairments might have good outcome.