Background: acute exacerbation of COPD is an acute event characterized by a worsening of the patient's respiratory symptoms (increase dyspnea, increase cough, increase volume sputum and purulent) that is beyond normal day to day. Respiratory infection is the most common cause and increase prevalence of antibiotic resistant of bacteria. Objectives: identify bacterial etiology and antibiotic resistant pattern of isolated organisms in exacerbation COPD. Patients and methods: prospective, crosssection study, included 112 patients admitted to department of respiratry medicine of general department hospital of Hai Duong provine from March 1, 2012 to February 28, 2013 that were diagnosed acute exacerbation COPD following GOLD criteria. Sample of spontaneously expectorated sputum for microbiological evaluation was obtained from all patients during admission and were collected before starting antibiotic treatment at the hospital. Antibiotic susceptibility testing was interpreted according to CLSI 2011 (Clinical and Laboratory Standards Institute guidelines). Results: (i) most common bacterial etiology in AE COPD were Streptococcus pneumoniae (27,2 percent), Haemophilus influenzae (20,4 percent), Pseudomonas aeruginosa (18,1 percent), Klebsiella pneumoniae (11,3 percent). (2) antibiotic resistant pattern: isolated ogarnisms there were high resistant prevalence with Ampicilin, Cefuroxim and Amikacin and high sensitivity prevalence with Piperacilin-Tazobactam, Cefoperazol-Sulbactam, Imipenem, Levofloxacin. Conclusion: the most common bacterial etiology were S. pneumoniae, H. influenzae, P. aeruginosa, K. pneumoniae, and high resistant prevalence with Ampicilin, Cefuroxim and Amikacin but high sensitivity prevalence with Piperacilin - Tazobactam, Cefoperazol - Sulbactam, Imipenem, Levofloxacin.