Abstract: AIM: To investigate the antimicrobial activity of linezolid, vancomycin and other antibacterials against 111 methicillin resistant staphylococcus aureus. METHODS: Broth dilution method was used to determine the minimum inhibitory concentrations (MICs) of linezolid, vancomycin and other antibacterials against 111 methicillin resistant staphylococcus aureus identified by cefoxitin.RESULTS: The resistant rates of 111 MRSA to β-lactam, erythromycin, aminoglycosides (netilmicin and gentamycin), fluoroquinolones (gatifloxacin, moxifloxacin and levofloxacin) and chloromycin were 100%, 92.8%, 99.1%, 91.9% -99.1%, 3.6%.All 111 MRSA were sensitive to linezolid and vancomycin, andMIC₅₀ and MIC₉₀ of vancomycin were 0.5 and 1 μg/mL, MIC₅₀ and MIC₉₀ of linezolid were 2 μg/mL.CONCLUSION: 111 MRSA were resistant to most antibacterials including β-lactam, erythromycin, aminoglycosides and fluoroquinolones. Linezolid and vancomycin have strong antimicrobial activity against MRSA.

Key words: linezolid, vancomycin, MRSA, antimicrobialactivity