ObjectiveTo evaluate the molecular epidemiological features of Acinetobacter baumannii (Ab) causing ventilatorassociated pneumonia（VAP）.MethodsSeven strains of Ab isolated from lower respiratory tract secretion of VAP patients were typied by pulsedfield gel electrophoresis (PFGE), and drugresistance of strains were detected.ResultsThe similarity of PFGE electrophoresis strips of 7 strains was 57%-100%, there were 4 PFGE patterns（A,B,C and D）, 2(28.57%) strains were for pattern A， B and D respectively, 1(14.29 %) strain was for pattern C. Ab had different drugresistance to 13 kinds of antimicrobial agents (ceftazidime, imipenem,tobramycin, etc.), all were pandrugresistant strains, pattern C strain was alldrugresistant strain.ConclusionPFGE typing can accurately and quickly trace the homology of nosocomial infection caused by Ab.