There is a higher incidence of status epilepticus in the older adult population that commonly presents as nonconvulsive status epilepticus (NCSE). NCSE most often corresponds to prolonged focal seizures with impaired consciousness with three main clinical presentations: i) an unexplained acute confusional state, ii) subtle eye, motor or behavioral signs or mood changes and iii) typical temporal or frontal seizures with impaired consciousness. Focal seizures without impaired consciousness or de novo absence status of late onset may also be met. The identified risk factors for NCSE onset are: a precession by a generalized tonic-clonic seizure, a known history of epilepsy, female gender, and an acute symptomatic cause or a known brain injury (especially a stroke sequelae). Diagnosis in this population may be difficult, as the clinical presentation is often not very suggestive (stupor, confusion, even coma), and requires an unrestricted use of EEG with an EEG diagnosis based on the EEG with now accepted criteria (so-called Salzburg EEG criteria). The treatment is based first on the injection of benzodiazepines and in the second line on intravenous or oral or gastric tube administration of antiepileptic drugs. It is not recommended to resort to an intubation-ventilation (except necessary to treat respiratory distress, multi-organ failure…). Prognosis is poor with about 30% mortality.