Abstract: OBJECTIVE To explore the influencing factors for nosocomial infection in the patients of closed psychiatric ward and put forward the prevention countermeasures. METHODS A total of 315 patients who were hospitalized in the closed psychiatric wards of Panzhihua Third People′s Hospital from Aug 2016 to Feb 2019 were enrolled in the study, the clinical data of the patients were retrospectively analyzed, the pathogens causing the nosocomial infection were analyzed, and the univariate analysis and multivariate logistic regression analysis were performed for the influencing factors for the nosocomial infection. RESULTS Of the 315 patients, 27 had nosocomial infection, with the infection rate 8.57%; the patients with respiratory tract infection were dominant among the patients with nosocomial infection.The influencing factors for the nosocomial infection in the patients of closed psychiatric wards included the clinical factors such as age, types of mental illness, types of psychotropic drugs, invasive operation, protective restriction, hand hygiene management, length of hospital stay and disinfection in wards as well as the auxiliary examination factors such as hemoglobin, albumin and the ratio of forced expiratory volume in one second（FEV1）to forced vital capacity（FVC）（P＜0.05）.Multivariate logistic regression analysis showed that the types of mental illness, number of psychiatric drugs, invasive operation, length of hospital stay, low level of hemoglobin, low level of albumin and FEV1/FVC were the influencing factors for the nosocomial infection in the closed psychiatric wards, and the protective restriction, hand hygiene management and disinfection in wards were protective factors. CONCLUSION There are a variety of influencing factors for nosocomial infection in the closed psychiatric wards, and it is an effective way to eliminate the high-risk factors so as to prevent the infection and promote physical and mental recovery of the patients.