Objective To understand the prevalence rate of nosocomial infection,location of infection,and use of antibiotics in hospitalized patients,so as to provide reference for the prevention and control measures of nosocomial infection. Methods The prevalence rate of all patients who were hospitalized from 0 to 24 hour on November 5,2020 were investigated by the review of real-time monitoring system combined with bedside investigation. Results In this investigation,totally 3 306 cases were expected to be investigated and 3 291 cases (99.55%) were actually investigated.There were 186 cases (201 times) of nosocomial infection.The prevalence rate of nosocomial infection was 5.65%,and the prevalence rate of cases was 6.11%.The departments with high incidence of nosocomial infection included intensive care unit (ICU) (29.63%),neonatal center (21.95%),hematology department (19.61%) and neurosurgery department (19.57%).The lower respiratory tract was the most common site of infection at 52.24%.Four type incisional surgical site infection was 13.33%.The detected microorganisms were mainly Gram-negative bacteria,including Acinetobacter baumannii and Klebsiella pneumoniae.The utilization rate of antibiotics in all patients was 41.84%.The utilization rate of the internal medicine system was 16.50%,and the utilization rate of the surgical system was 25.34%. Conclusion According to the prevalence of nosocomial infection,it is necessary to strengthen the prevention and control of key department and key populations,strictly manage antibacterial drugs,improve the pathogen examination rate,so as to reduce the incidence of nosocomial infection.