ObjectiveTo investigate the nationwide prevalence of healthcareassociated infection (HAI), and establish the related indexes of HAI.MethodsA crosssectional survey was conducted through combination of bedside investigation and medical record reviewing, the prevalence of HAI in hospitals of National HAI Surveillance System and other hospitals voluntarily participated in the survey were investigated according to unified survey program.ResultsA total of 1 008 584 patients in 1 766 hospitals participated in the survey, 26 972 cases of HAI occurred, prevalence rate of HAI was 2.67%, antimicrobial usage rate was 35.01%. Difference in prevalence rates of HAI and antimicrobial usage rates among hospitals with different number of beds were both significant (χ2=1 599.21, 3 458.40，respectively, both P＜0.01）. The main infection sites were lower respiratory tract (47.53%), urinary tract (11.56%) and surgical site(10.41%). A total of 13 784 pathogenic strains were isolated, the top five pathogens were Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus. Prevalence rate of HAI and prophylactic antimicrobial usage rate in patients receiving operation of class Ⅰincision were 1.01% and 27.99% respectively, difference in prophylactic antimicrobial usage rates in patients receiving operation of class Ⅰ incision at hospitals with different number of beds were significant (χ2=400.34，P＜0.01）；among patients receiving antimicrobial prophylaxis, percentage of specimens sending for bacterial detection was 45.89%, difference in bacterial detection rates in hospitals with different number of beds were significant (χ2=9 189.90，P＜0.01）. Hospital with more than 900 beds had the highest prevalence rate of HAI（3.36%）, lowest usage rate of antimicrobial agents（32.35%）, and highest bacterial detection rate（56.03%）.ConclusionMultiple indexes of this crosssectional survey revealed that HAI management in China has achieved remarkable results; meanwhile, calculation of the percentile distribution of each index is convenient for selfevaluation for HAIrelated work in each hospital.