Abstract: 　Objective　To explore the clinical characteristics, diagnosis and treatment of SCN8A gene mutation associated epileptic encephalopathy. Method　The clinical data of SCN8A gene mutation associated epileptic encephalopathy in 2 children were retrospectively analyzed, and the related literature was reviewed. Results　Two boys had psychomotor retardation and was onset with convulsions. The mutation of SCN8A gene was confirmed in 2 patients by gene test. The age at onset was 3.5 months after birth in case 1. Because of the increase of seizures with the use of lethiracetam, it was replaced by topiramate and traditional Chinese medicine, but effect in the control of seizures was not ideal. At the age of 2 years and 9 months, the child had frequent seizures, accompanied by severe regression of language and motor development and poor swallowing function. After addition of lamotrigine, the seizures was stopped and his swallowing function was returned to normal, and the movement and language began to recover gradually. The age at onset was 2 months after birth in case 2. The seizure frequency was reduced but not completely controlled after the treatment of topiramate. Due to reduced sweating and increased body temperature in summer as well as increased seizure frequency, topiramate was discontinued and replaced by levetiracetam, but the seizure frequency was increased. Thus, levetiracetam was discontinued and was replaced by sodium valproate, and the seizure frequency was reduced. After combined use of oxcarbazepine, seizures were completely controlled, and no recurrence was observed for two and a half years of follow-up. Case 2 suffered from delayed development and poor swallowing function from birth to now. Conclusions　SCN8A gene mutation leads to early onset of epilepsy often accompanied by mental/developmental retardation and delayed language development. When the seizures are severe, abnormal swallowing function occurs. The disease responds well to sodium channel blockers.

Key words: SCN8A gene;　epilepsy;　sodium channel blocker;　encephalopathy