Abstract: Objective To establish a genetic typing maps for 95 stains of Brucella in China by pulsed-field gel electrophoresis(PFGE).Methods SeaKem Gold agarose plug was used to purify the intact chromosome DNA from 95 isolates of Brucella selected from different areas and years,including 19 reference stains.Then the chr omosome DNAs were digested with restriction endonuclease XbaI and the fragments were separated by PFGE.Results Genetic DNA of 19 reference type strains digested with low-cleavage-frequency restriction enzymes XbaI produced PFGE profiles that distinguished these strains to the level of species.For field strains isolated in China,chromosomal DNAs in agarose plugs were digested with XbaI,resulting in 15 to 25 bands.Thirty-nine distinctive PFGE patterns in the range of 20 to 500 kb were noted among 76 isolates by PFGE.Conclusion PFGE patterns,which can be used to classify and identify Brucella,can be used in molecular epidemiological research of Brucella.