ObjectiveTo investigate the distribution and drug resistance of common gramnegative bacilli in intensive care unit （ICU） in a hospital.MethodsThe species and drug susceptibility test of the common gramnegative bacilli isolated from ICU between 2008 and 2010 were analyzed retrospectively. Bacteria were identified and performed antimicrobial  susceptibility test with VITEK2（bioMerieux） system. The date were analyzed by the software “WHONET5.5”.ResultsOf 1 551 gramnegative bacilli isolates, 68.06% were isolated from sputum; among the common gramnegative bacilli, the first one was Acinetobacter baumannii, which accounting for 25.40% (394 strains), followed by  Klebsiella pneumoniae (21.66%,336 strains), Escherchia coli (16.76%,260 strains), and Pseudomonas aeruginosa (15.86%, 246 strains),etc; 198(58.93%) strains of Klebsiella pneumoniae and 174(66.92%) of Escherichia coli were extendedspectrum βlactamaseproducing  strains. The common gramnegative bacilli had very low resistant rates to  piperacillin/tazobactam, imipenem, cefoperizone/sulbactam and amikacin, the resistant rates was 19.23%-31.73%,9.23%-37.40%, 14.88%-32.23%, and 22.92%-27.66%,respectively.ConclusionMultidrug resistance among the common gramnegative bacilli in ICU is very serious . In order to reduce the emergence of drugresistant bacterial strain, it is important to use  antimicrobial agents correctly based on drug susceptibility test result.