The main reason for the existence of the immune system in humans is to identify and destroy pathogenic bacteria and harmful substances (similar to the guard system in a country or region, which is used to identify and punish wrongdoers). Among them, antibodies, as an important component of the immune system, are used to destroy viruses, bacteria and tumor cells under normal conditions; however, in certain abnormal conditions (when there is prolonged heavy stress, exertion, infection or the presence of tumors in the body), it can lead to disorders in the body’s immune system. For example, the immune system activates abnormally and produces a large number of antibodies (these antibodies lose their normal recognition function and become unrecognizable) which in turn attack the normal proteins (including intracellular and extracellular component proteins) of one or more of our own organs, resulting in abnormal organ function, which is called autoimmune disease (frankly, a disease in which we immunize ourselves). When this abnormal immune attack occurs in brain tissue, it is called autoimmune encephalitis. Autoimmune encephalitis is a large group of treatable and effective diseases with complex but mostly specific clinical manifestations. Currently, 13 types of autoimmune encephalitis are recognized, among which anti-NMDA receptor encephalitis is the most common, followed by antibody VGKC complex (LGI1, CASPR2) antibody encephalitis, anti-AMPA receptor antibody encephalitis, and anti-GABAb receptor antibody encephalitis.