ObjectiveTo investigate the distribution and change in drug resistance of clinical isolates in a hospital from 2006 to 2008.MethodsBacteria were isolated and identified by routine methods， antimicrobial susceptibility test was carried out by KirbyBauer method.ResultsA total of 3 499 clinical isolates were collected, grampositive and negative bacteria accounted for 24.12% (844 strains) and 75.88% (2 655 strains) respectively. 60.29% (208/345) of Staphylococcus aureus isolates were identified as methicillinresistant Staphylococcus aureus. Isolates of Enterobaceriaceae were still highly sensitive to carbapenem antibiotics. ESBLsproducing strains accounted for 45.23%(403/891) in Escherichia coli and 38.92% (130/334) in Klebsiella spp. respectively; Pseudomonas aeruginosa isolates showed relatively higher resistant rates to imipenem and meropenem,  which was 41.06% and 34.52% respectively, Acinetobacter spp. isolates showed relatively lower resistant rates to imipenem and meropenem, which was 15.52% and 31.90% respectively.ConclusionThe prevalence of MRSA and ESBLsproducing strains is high; surveillance of antimicrobial resistance can help clinicians use antimicrobial agents rationally and control the transmission of drugresistant strains.