Objective:To study the distribution and structure of gene cassettes of class I integron in Acinetobacter baumannii in the First Affiliated Hospital of NJMU and explore the relationship between integron and its resistance. Methods:K-B tests were performed to detect the susceptibility of 77 isolates of Acinetobacter Baumannii randomly selected from the hospital to 18 kinds of antimicrobial agents,class 1 integrase gene(intI 1) and its variable region were amplificated by PCR,the products were analyzed by restriction endonucleases and sequenced. Results:77 isolates from different samples were serious antibiotic resistance. 49 of 77(63.64%) isolates were found containing class 1 integron and 91.84%(45/49) of the intI 1 positive strains owned the variable region. Four different sizes(0.8 kb,1.8 kb,2.3 kb and 3.0 kb) of the variable region of integrons were amplified. Sequencing results identified four gene cassettes arrays:aacA4,dfrXII-orfF-aadA2,aacA4-catB8-aadA1 and aacC1-orfX-orfX-orfX’-aadA1a. Significant association was demonstrated between integron carriage and resistance to antibiotics in Acinetobacter baumannii. Conclusion:class I integron is closely related to the resistance of Acinetobacter baumannii and plays an important role in its multi-drug resistance.