Abstract: OBJUECTIVE To construct the risk management model of ICU system, clarify the key points of prevention and control of nosocomial infection, and improve the efficiency of resource utilization, reduce the incidence of healthcare-associated infection（HAI）.METHODS By constructing the risk management model of ICU system, the extremely high-risk ICU was screened out. Aiming at the secondary assessment of extremely high risk ICU, the high risk processes were selected for intervention, and the incidence of nosocomial infection and the detection rate of multidrug resistant bacteria in nosocomial infection were compared before and after intervention.RESULTS The neurology ICU had the highest risk, and it was evaluated for two times. The high-risk process was selected out for further intervention. After the implementation of risk assessment, there was no significant difference in age, gender, diabetes and hypertension between before and after intervention. The incidence of HAI significantly decreased from 23.26%（20/86） to 9.82%（11/112）（P＜0.05）. The incidence rate of MDRO in HAI decreased from 5.29‰（6/1 135） to 0.94‰（1/1 069）（P＜0.05）, and the average per capita hospitalization days decreased from 13.20（1 135/86） to 9.54（1 069/112） days.CONCLUTION The construction of the risk management model of ICU system, evaluation of high-risk departments and high-risk processes, and targeted interventions can effectively optimize the allocation of resources, reduce the occurrence of HAI and ensure the safety of doctors and patients.