Abstract:Objective：Nosocomial infection surveillance system is a system that obtains various infection-related data by means of informatization，so as to give early warning of possible infection. Understand the impact of nosocomial infection surveillance systems on the incidence of nosocomial infections. Methods：A retrospective analysis of the nosocomial infection monitoring data of a certain grade A tertiary hospital from 2013 to the end of 2021，including the incidence of nosocomial infection in inpatients，the infection rate of Class I surgical incisions，the rate of device-related infection and multidrug resistance bacterial detection rate. The chi-square test was used to compare the differences between the data. Results：From 2013 to 2021，the incidence of nosocomial infection in hospitalized patients decreased from 2.81% to 1.76%（P=0.000）. Infection rates for Class I surgical incisions peaked twice in 2015 and 2018. After 2018，it decreased year by year，and it was 0.20% in 2021，which was significantly different from 0.71% in 2018（P=0.000）. The incidence of catheter-related bloodstream infection decreased from 2.89‰ in 2013 to 0.00‰ in 2021（P=0.001）. The rate of ventilator-associated pneumonia decreased from 3.61‰ to 0.88‰（P=0.020）. The incidence of catheter-related urinary tract infection decreased from 1.20‰ to 0.62‰（P=0.241）. The detection rate of methicillin-resistant Staphylococcus aureus decreased year by year，from 50.41% to 40.80%. Conclusion：Nosocomial infection monitoring system can effectively reduce the incidence of nosocomial infection，improve medical quality and ensure patient safety.