Abstract: RP-HPLC was applied to the determination of lactoferrin,which is used as a food additive.Sample of lactoferrin was dissolved with 0.5 mol·L-1 NaCl solution and diluted to an appropriate concentration with the same solvent.After filtration on 0.45 μm filtration membrane,the solution was used for HPLC analysis.The CAPCELL SG300 C18 chromatographic column was used for separation.Mixtures containing acetonitrile,0.5 mol·L-1 NaCl solution and trifluoroacetic acid mixed in different ratio were used as the mobile phase in gradient elution.UV-detection at the wavelength of 280 nm with DAD was adopted in the detection.Retention time and its characteristic UV-absorption spectra were the basis for qualification of lactoferrin.External standard method was used for the determination of lactoferrin.Linear relationship between values of peak area and mass concentration of lactoferrin was obtained in the range of 10.0-100.0 mg·L-1.Its lower limit of determination (10S/N) was found to be 5.0 mg·kg-1.