Objective:To establish a method for the determination of oleanolic acid in She medicine Clematis florida var. plena. Methods:The HPLC method was carried on a Lanbo-Kromasil C18 chromatography column using acetonitrile-water ( 86∶ 14 ) as the mobile phase. The detection wavelength was 205 nm, the flow rate was 1. 0 ml·min-1 , and the column temperature was 25 ℃. Re-sults:The calibration curve of oleanolic acid was linear within the range of 0. 52-15. 60μg (r=0. 999 9). The average recovery of oleanolic acid was 92. 13%(RSD=3. 0%, n=9). Conclusion:The method is simple, rapid, accurate and reproducible, which can be used as an ideal method for the quality control of She medicine Clematis florida var. plena. .