Abstract:A method was proposed for the determination of oleanolic acid and ursolic acid from Rubus suavis－ simus S.Lee by high performance liquid chromatography. The optimization of chromatographic analysis condition and sample pretreatment were studied. The sample was extracted by ethanol. The impurity was removed by ethanol extraction and water precipitation. The separation was completed by using Hypersil Gold C18（250 mm× 4.6 mm，5 μm）column with carbinol and 0.2 % acetic ammonium solution （83 ∶ 17） as the mobile phase at a flow rate of 0.6 mL/min， and the detection wavelength was 210 nm. The quantification was performed by the ex－ ternal standard method. Under these conditions， oleanolic acid and ursolic acid were completely separated， and it showed good linearities with their concentrations ranged from 2.23 μg/mL to 112 μg/mL and from 1.84 μg/mL to 92 μg/mL with correlation coefficients（R2）more than 0.999， and the detection limits were 0.04 and 0.08 g/kg. The recoveries were in the range of 92 %-102 % at 3 spiked levels with RSDs（n=6）of 0.8 %-3.8 %.