ObjectiveTo investigate the positive rate of class Ⅰ integrons and drugresistance of Stenotrophomonas maltophilia. MethodsSixty strains of Stenotrophomonas maltophilia were clinically isolated between July, 2006 and December，2007，the genes of intⅠ, qacE△1sul 1 of these strains were analyzed by PCR and antimicrobial susceptibility tests were performed by microbroth dilution method.ResultsThe positive rate of class Ⅰ integrons was 13.33% (8/60), only 80% Stenotrophomonas maltophilia were sensitive to minocycline，trimethoprimsulfamethoxazole and levofloxacin. ConclusionThe Stenotrophomonas maltophilia is an important pathogen in nosocomial infection, which has multipledrug resistance, and class Ⅰ integrons genes can promote the spread of bacterial resistance.