RÉSUMÉ
Objective The study analyse the multi-drug resistance and epidemiological investigation in Acinetobacter baumannii.Methodes Using,multi-drug resistance gene test,three-dimension test,membranes active efflux test studied multi-drug resistance and epidemiological investigation.The genetype were analyzed by Amplified Fragment Length Polymorphism(AFLP).The strains' homology were researched by multi-gene cluster analysis methods.Results Cluster analysis show that the result of drugsensitive test,multi-drug resistance gene test and AFLP are accordant.The study find at least 3 clones by multi-gene cluster analysis methods.AFLP show that all of the multi-drug-resistance of A.baumannii evolutes from a clone.Conclusions The study combined with clinical practice find that ICU in Ningbo No.2 Hospital now is the core of the arises,evolution,transmission of A.baumannii.Strengthening management of ICU is very important to pretect the prevalence of Acinetobacter baumannii in nosocomial infection.