ObjectiveTo investigate the prevalence of healthcareassociated infection (HAI) in a hospital in 2013-2015, and provide reference for the improvement of HAI management. MethodsPrevalence rates of HAI among patients in the First Affiliated Hospital of Zhengzhou University in 2013-2015 were investigated with crosssectional survey method, prevalence rates of HAI and constituent ratios of  HAI sites in patients of different genders and different age groups were analyzed. ResultsIn 2013-2015, 29 605 patients should be investigated, 29 581(99.92%) were actually investigated. Prevalence rates of HAI in 2013-2015 were 2.83%,2.14%,and 1.73%，respectively, difference was  significant(χ2=27.521，P<0.01）, which showed a downward trend year by year. Prevalence rates of HAI in male was significantly higher than that of female (2.47% vs 1.98%, χ2=7.954, P<0.01). The prevalence rates of HAI in the age dimension was roughly Ushaped distribution in 2013-2015. Prevalence rates of HAI in ≥70 age group was the highest( 4.15%), in 0-30 age group decreased with age, in > 30 age group increased with  age. The top three sites for prevalence of HAI were lower respiratory tract (45.67%), upper respiratory tract (9.92%), and urinary tract (8.52%). ConclusionThe prevalence rates of HAI decreased year by year in 2013-2015, which suggests that HAI prevention and control measures are effectively implemented.