ObjectiveTo understand the distribution and change in drug resistance of common pathogens before and after the implementation of special rectification activity on antimicrobial use in 2011-2015, and provide guidance for clinical application of antimicrobial agents. MethodsAntimicrobial use in hospitalized patients and pathogens isolated from patients in a hospital from 2011 to 2015 were collected, changing trend of resistance rates of major pathogens to commonly used antimicrobial agents was analyzed. ResultsFrom 2011 to 2015, antimicrobial utilization rate in hospitalized patients dropped from 75.84% to 37.35%, antimicrobial use density decreased from 59.53 per 100 patient days to 33.63 per 100 patient days, both showed a downward trend (both P<0.05). A total of 10 091 strains of pathogens were isolated, 2 338 (23.17%) of which were grampositive bacteria, 7 110(70.46%) were gramnegative bacteria, and 643(6.37%) were fungi. The top five pathogens were Escherichia coli (20.85%), Klebsiella pneumoniae(15.90%), Pseudomonas aeruginosa (11.70%), Staphylococcus aureus (7.35%), and Acinetobacter baumannii(6.82%). Resistance rates of major pathogens to commonly used antimicrobial agents decreased year by year（P＜0.05）, resistance rates of Escherichia coli and Klebsiella pneumoniae to piperacillin/tazobactam, cefoxitin, and amikacin declined most obviously(all<4% in 2015); compared with Acinetobacter baumannii, Pseudomonas aeruginosa had higher sensitivity to commonly used antimicrobial agents, resistance rates to piperacillin/tazobactam, cefoperazone/sulbactam, ceftazidime, cefepime, amikacin, and ciprofloxacin decreased obviously, resistance rate to above antimicrobial agents was <20%, to carbapenems was higher than other commonly used antimicrobial agents. Resistance rates of Acinetobacter baumannii to amikacin, levofloxacin decreased most obviously, to meropenem and imipenem increased obviously, in 2015 were both above 50%. Resistance rate of Staphylococcus aureus to fluoroquinolones declined most obviously(<2%), vancomycinresistant strains were not found. ConclusionAfter the implementation of special rectification activity, resistance rates of common pathogens decreased with the decline of antimicrobial use, rational use of antimicrobial agents may be related to delaying bacterial resistance.