Abstract: Objective To investigate the distribution, diagnosis and treatment of patients with mental disorders in emergency department of a large general hospital. Methods Records of patients with mental disorders, who came for psychiatric diagnosis in the emergency department of West China Hospital of Sichuan University, during 1 July 2014 to 30 June 2015 were reviewed. Data about demographic characteristics, diagnosis and treatment of those patients were extracted and analyzed. Results A total of 520 patients were included in the analysis: 212 male (40.8%) and 308 female (59.2%). Three most common disorders were “Schizophrenia, Schizotypal disorder and Delusional disorder” (175 cases, 33.7%), “Mood disorder” (106 cases, 20.4%) and “Neurosis, Stress related and Somatoform disorder” (113, 21.7%). 50 (9.6%) patients were not confirmed with a diagnosis. Conclusion Common mental disorders in the emergency service of this hospital include “Schizophrenia, Schizotypal disorder and Delusional disorder”, “Mood disorder”, and “Neurosis, Stress related and Somatoform disorder”. Diagnosis of some patients is unclear. A wide range of treatment regimen should be made available.