Abstract: OBJECTIVE To establish an HPLC method for the determination of moxifloxacin in rat plasma, and validated for pharmacokinetic study. METHODS The moxifloxacin was extracted from plasma by dichloromethane. Chromatographic separation was carried out on ZORBAX Edipse XDB-C₈ column(150 mm×4.6 mm, 5 μm) with water-0.1% trifuoroacetic acid-acetonitrile(40∶35∶25) as the mobile phase at a flow rate of 1.0 mL·min^-1. The detection wavelength was 296 nm and the column temperature was 30 ℃. RESULTS The linear range was 0.05-10.00 μg·mL^-1(r=0.999 6). The lowest detectable limit was 0.05 μg·mL^-1. The recovery of the method was 99.3%-106.0%, and the extraction recovery was 88.1%-94.1%. RSDs of inter- and intra-day precisions were both less than 10%. The profile of moxifloxacin in vivo fitted a two-compartment model. CONCLUSION The method is simple, economic and accurate, which could be used for the pharmacokinetic study of moxifloxacin.