Anti-NMDA receptor encephalitis is the most common curable non-infectious autoimmune encephalitis，but because of the lack of recognition in the clinic, usually been misdiagnosed as other causes of encephalitis. Therefore, it is urgent to establish a database of anti-NMDA receptor encephalitis in Chinese population. The multi-center, prospective clinical trial of anti-NMDA receptor encephalitis in China's , combined with Beijing Xuanwu hospital, Beijing Tiantan Hospital, Beijing Children's Hospital and other hospitals around the country, by screening the NMDA receptor antibody and summarizing the cases analysis, in order to provide evidence for clinical diagnosis and treatment of anti-NMDA receptor encephalitis.