Abstract: Objective Todetect the genotypes of Acinetobater baumannii isolatedfromICU environments, and provide basis for hospital infection investigation. Methods The environmental samples fromsurgical ICU, neurological ICU and respiratory ICU were collectedevery twoweeks continually fromOctober 2010 toOctober 2011 and Acinetobacter baumannii strains were isolated. The antibiotic susceptibility of 15 kinds antibiotics were detectedby V- teck. The genotype polymorphismof multi-drug resistant Acinectobacter baumannii stains was examinedby pulsed-fieldgel electrophoresis (PFGE). Four strains frompatients were selectedas the genotype control. Results A total of 7 878 samples were collected. Among 229 Acinetobacter baumannii stains, the isolatedrate of multi-drug resistant strains was 1.13% (89/7 878). The distribution of multi-drug resistant Acinectobacter baumannii in three ICU hadnosignificant difference (P＞ 0.05). There was nocentral tendency of the genotypes among the 89 multi-drug resistant isolates, of which three types (class A, B and C) were clusteredat the similarity of 40%. The subtype A2 was the main type (24.7%), followedby the subtype A1 and A8, which accountedfor 15.1% and 15.1%, respectively. Nocentral tendency was showedin time and space. The patients and the environmental isolates with the similarity of 90% in the same or different ICU showednoepidemiological association. Conclusion During the monitoring period, the genotypes polymorphismof antibiotic resistant Acinectobacter baumannii isolatedfromthree ICU environment shownocentral tendency, which suggests that the isolates come fromenvironmental flora under antibiotic pressure.