Abstract: Objective To investigate the etiology and prognosis of epileptic encephalopathies(EEs) in children. Methods We reviewed the clinical data of patients with EEs in childhood to analyze their etiologies. The therapeutic effect and development outcome were followed up. Results We enrolled 234 cases of EEs, including West syndrome (n=92), Dravet syndrome (n=53), Lennox-Gastaut syndrome (n=32), Landau-Kleffner syndrome (n=15), Ohtahara syndrome (n=13), epileptic encephalopathy with continuous spike-and-wave during sleep (n=10), myoclonic-atonic epilepsy (n=2), Rasmussen syndrome (n=2), and the unclassified 15 cases. Genetic etiology accounted for 67.9% (31.2% confirmed by gene detection), structural for 12.0%, infectious for 4.7%, metabolic and immunogenic for 0.9% respectively, and 19.2% remained unknown. The effective rates of antiepileptic drugs (AEDs), ketogenic diet, surgery and vagus nerve stimulation (VNS) were 33.8% (79/234), 47.3% (35/74), 60.0% (3/5) and 44.4% (4/9) respectively.The effective rate of comprehensive treatment (drug treatment alone or ketogenic diet/surgery/VNS based on drug treatment) was 48.7%. Development outcome was that 223 cases (95.3%) showed developmental retardation in the first intelligence assessment after onset and 215 cases (91.9%) showed developmental retardation after treatment (median follow-up duration: 44 months). Conclusion Genetic etiology was the primary cause of EEs. AEDs were effective in only one-third of cases, and the incidence of developmental retardation was high, leading to poor prognosis. Multidisciplinary diagnosis and treatment (MDT) played a key role in the diagnosis and management of EEs.