Objective To understand the changing trend of healthcare-associated infection (HAI) monitoring indexes in 50 secondary and higher grade hospitals in a city for 6 consecutive years from 2017 to 2022. Methods Infection monitoring indexes from 50 secondary or higher grade hospitals in the city for 6 consecutive years were collec-ted, and changing trend of HAI monitoring indexes were compared. Results The number of full-time HAI management professionals increased from 91 in 2017 to 165 in 2022. The utilization rate of HAI information system increased from 17.00% in 2017 to 54.00% in 2022. In 6 consecutive years from 2017 to 2022, the incidence of HAI (0.91% vs 0.59%), prevalence rate of HAI (2.36% vs 1.08%), infection rate of class Ⅰ incision surgical site infection (0.33% vs 0.16%) in 50 secondary or higher grade hospitals all showed downward trends, while health care workers' hand hygiene compliance rate showed an upward trend (61.03% vs 85.04%). Incidences of vascular cathe- ter-related bloodstream infection, ventilator-associated pneumonia, and catheter-associated urinary tract infection all showed downward trends. Incidence of HAI, prevalence rate of HAI, health care workers' hand hygiene compliance rate, and incidence of ventilator-associated pneumonia in tertiary hospitals were all higher than those in secon-dary hospitals, while surgical site infection rate of class Ⅰ incision in secondary hospitals was higher than that in tertiary hospitals, with statistically significant differences (all P < 0.001). Conclusion Standardizing the monitoring of HAI, as well as improving the prevention and control system and measures of HAI according to the monitoring results can reduce the incidence of HAI.