OBJECTIVE： To provide reference for clinical rational use of antibiotics. METHODS： The use of antibiotics in our hospital from Jan. 2012 to Dec. 2015 was analyzed， the DDDs was calculated， bacterial resistance rates over the same period was analyzed， and the relationship between them were analyzed with Pearson method. RESULTS： During 2012-2015， the top 3 antibiotic DDDs in our hospital were cephalosporins， macrolides and quinolones； bacterial with the top 5 detection rate was Escherichia coli， Pseudomonas aeruginosa， Klebsiella pneumoniae， Acinetobacter Bauman and Staphylococcus aureus； the DDDs of imipenem cilastatin sodium showed a positive correlation with the resistance rate of P. aeruginosa （r＝0.95，P＜0.05） and the total resistance rate of Gram-negative bacteria （r＝0.98， P＜0.05）， meropenem showed a positive correlation with the resistance rate of K. pneumoniae （r＝0.97，P＜0.05）， piperacillin sulbactam sodium showed a negative correlation with the resistance of P. aeruginosa （r＝－0.98，P＜0.05）. CONCLUSIONS： DDDs is correlated with the antibiotic drug resistance rate of bacteria， which should be planned and scientific used to reduce the bacterial resistance.