Abstract: Objective To statistic and analyze utilization of antibiotic drugs and resistance rate of gram negative bacteria in a hospital during 2011-2013, to reduce bacterial resistance and to provide references for clinical rational use of antimicrobial drugs. Methods Retrospective investigation method was used to statistically analyze the pathogenic bacteria culture results,antimicrobial cumulative frequency of each categories and results of drug resistance test. Results Ranked the top five gram negative pathogens in 2011-2013 year were Escherichia coli,Bauman Acinetobacter,Pseudomonas aeruginosa,Klebsiella pneumoniae and Enterobacter cloacae, the proportion has no obvious changed in each year. The total DDDs of antibacterial drugs reduced year by year, down from 255456.37 DDDs in 2011 to 155024.25 DDDs in 2013, cephalosporin and enzyme inhibitors and macrolide consumption ranked increased year by year, the three or four generation cephalosporins and quinolones such amount was reduced year by year, antifungal fungi and carbapenem ranking had no obvious changed. All kinds of bacteria were high resistant to amoxicillin, reached 100% in 2013, Bauman Acinetobacter and Pseudomonas aeruginosa to piperacillin tazobactam resistant rate increased year by year, Bauman Acinetobacter to beta lactam antibiotics drugs showed a gradual trend of drug resistance. Conclusion The frequency of antimicrobial drug use showed a declining trend in our hospital, and drug-resistant bacteria rate increased, in order to reduce the resistance present form,we need to more rational use antimicrobial agents.