ObjectiveTo investigate the antimicrobial use in patients at different scales of hospitals of China in 2010.MethodsAn oneday pointprevalence survey on antimicrobial use in hospitalized patients was conducted with crosssectional investigation method.ResultsThe daily antimicrobial use rate in 407 208 inpatients at 740 hospitals was 49.63%, 49. 99% of which were for therapeutic use, 39.17% for prophylaxis, and 10.84% for both. Of all patients receiving antimicrobial agents, 67.96% received monotherapy regime, 30.08% received two combined and 1.96% received three or more drug combined. 29. 21% of patients receiving therapeutic antimicrobial agents sent samples for pathogenic detection. Antimicrobial usage rate in teaching hospitals was lower than nonteaching hospitals(χ2=100.53，P=0.00), antimicrobial usage rate had a “stepbystep” rise among hospitals with ≥900,600899,300599,＜300 beds(χ2=571.90，P=0.00；χ2=579.38，P=0.00；χ2=36.11，P=0.00). Departments with high use of antimicrobial agents were pediatrics（85.50%）, general intensive care unit（81.95%） and respiratory diseases department（76.99%）.ConclusionInpatients in 740 hospitals had high usage rate of antimicrobial agents, prophylactic and combined use is more, sample for pathogen detection was less, it is necessary to strengthen the management of antimicrobial rational use.