Abstract: Objective: To summarize and analyze the clinical manifestations, EEG features, laboratory and imaging features of 50 patients with autoimmune encephalitis. Methods: Clinical data of patients diagnosed with AE in the Department of Neurology of Jiangsu Provincial People's Hospital from November 2019 to March 2023 were retrospectively analyzed. Groups were grouped according to different antibody encephalitis, and the baseline data characteristics were compared among the groups. They were grouped according to whether the first symptom was seizure or not, and the baseline data characteristics between the two groups were compared. Results: A total of 50 patients were included in the study, with males accounting for 62% (31/50) and females 38% (19/50). The average age of onset was 46±17.89 years old. The most common first symptom was epileptic seizure (56%, 28/50), the most common clinical presentation was epileptic seizure (70%, 35/50), and the characteristic clinical features of encephalitis with anti-leucine-rich glioma inactivated 1 protein (LGI 1) antibody were facial arm dystonia epilepsy and hyponatraemia（P =0.033）. 80% (40/50) of patients developed EEG abnormalities that presented as diffuse or/focal slow wave or epileptiform discharges. 66% (33/50) of patients had abnormal cranial MRI, and 63.64% (21/33) had abnormal temporal lobe or hippocampus. The first symptom of epilepsy was higher in males (P =0.001). Conclusion: The clinical characteristics of AE are varied. Hyponatremia and facial arm dystonia epilepsy are the characteristic symptoms of anti-LGI 1 antibody encephalitis. Patients with AE who develop general tonic-clonic seizures or persistent epileptic states during the course of the disease need to be aware of the risk of continuing seizures or developing chronic epilepsy after remission. The majority of patients with AE have abnormal electroencephalogram, but lack of specificity, with diffuse or/focal slow wave or epileptiform discharges. Most of the imaging findings showed abnormal temporal lobe signals. Key words: autoimmune encephalitis; Autoimmune epilepsy; Electroencephalography;