ObjectiveTo evaluate in vitro activity of antimicrobial agents against multidrugresistant Acinetobacter baumannii (MDR A.baumannii).Methods224 MDR A.baumannii strains isolated from specimens of clinical departments in a hospital between January and May 2013 were identified and performed antimicrobial susceptibility testing.Results224 MDR A.baumannii strains were mainly isolated from respiratory disease department(21.43%), neurosurgical department(16.07%), neurosurgical intensive care unit(12.50%), and neurology department(12.50%). The major specimens of A.baumannii was sputum(57.14%),the next were tracheal intubation(16.52%) and drainage fluid(9.82%). MDR A.baumannii strains were sensitive to tigecycline, the resistant rate to minocycline was 7.14%,to the other eight antimicrobial agents were all ≥75%, resistant rate to cefotetan was up to 98.21%.ConclusionTigecycline is highly effective against MDR A.baumannii in this hospital.