ObjectiveTo study the distribution and antimicrobial resistance of pathogens in AIDS patients with bacterial  pneumonia.MethodsPathogens isolated from 433 AIDS patients  with bacterial pneumonia in a  hospital from January  2008 through  February  2010 were analysed .ResultsA total of 106 bacteria strains  were isolated from 433 patients, the main source was sputum (90 strains, 90.90%) , followed by pleural effusion and pneumocentesis histological samples. Of all  pathogens ,  77 strains (72.64%) were gramnegative bacilli，30 (38.96%) of which were nonfermentative bacteria, 47 (61.04%) were Enterobacteriaceae  bacteria;  28 of 106 (26.42%) were grampositive cocci , the majority were coagulase negative Staphylococcus (15 strains,53.57%); 1 of 106 (0.94%) was fungi. The ESBLs producing  rate of Escherichia coli, Klebsiella pneumoniae, and  Pseudomonas aeruginosa was 72.73%(16/22), 46.15% (6/13) and 20.83%(5/24) respectively. Antimicrobial resistant rate of Escherichia coli and Klebsiella pneumoniae to imipenem was 0.00%. Antimicrobial resistant rate of Pseudomonas aeruginosa to imipenem was 8.33%. Of all gramnegative bacilli , except for Stenotrophomonas maltophilia， antimicrobial resistant rate to the third and fourth generation cephalosporins was > 60.00% and > 53.00% respectively. The resistant rate of Stenotrophomonas maltophilia to commonly used cephalosporins was very high. MRCNS showed multidrugresistance except high sensitivity to vancomycin , there was no resistant strain to vancomycin in all MRCNS.ConclusionThe main pathogens in AIDS patients with bacterial pneumonia are gramnegative bacilli, and  drug resistance is obvious. Antimicrobial  susceptibility test result  can provide reference for clinical application of antimicrobial agents .