摘要Autoimmune encephalitis(AE)is a type of encephalitis caused by autoimmune disease.AE was included on a list of the first batch of 121 rare diseases published by the Chinese National Health Commission on 11th May 2018.Currently,patients with AE account for 10％-20％of encephalitis cases,with 54％-80％of those cases classified as the anti-N-methyl-D-aspartate receptor(NMDAR)type,which is the most common type.[1]In 2010,China reported the first case of a patient with anti-NMDAR type AE.Although new neural autoantibody biomarkers and awareness among doctors have increased in recent years,reports of patients with AE are rare.[2]There are also many other differential diagnoses,such as toxic/metabolic encephalopathy,neoplasm,epilepsy,and functional neurological disorders,that might be misdiagnosed.Hear,we report a patient whose diagnosis of anti-NMDAR type AE with severe pneumonia was initially misdiagnosed.