OBJECTIVE: To provide reference for rational drug use in the clinic. METHODS: By retrospective investigation, antibiotic use density (AUD) and sensitivity rates of Acinetobacter baumannii to commonly used antibiotics in the inpatients were analyzed statistically in our hospital during 2010-2014, and the relationship between AUD and drug resistance of A. baumannii were analyzed with Pearson and Spearman method. RESULTS: 2 537 strains of A. baumannii were detected in clinical microbiological specimen of inpatients from our hospital during 2010-2014. The sensitivity rates of A. baumannii to meropenem and imipenem were negatively correlated to AUD (r=0.990,0.930,P<0.05). The sensitivity rate of A. baumannii to trimethoprim-sulfamethoxazole, ciprofloxacin, minocycline, piperacillin-tazobactam, cefepime, cefoperazone-sulbactam, ceftazidime and levofloxacin were not correlated to AUD. CONCLUSIONS: The use of carbopenems is an important factor to drug resistance of A. baumannii.