Abstract: An efficient,accurate and stable method for the determination of ursolic acid and oleanolic acid has been established.Then the contents of ursolic acid and oleanolic acid in Paulownia leaves in Xiangxi were determined.High performance liquid chromatography (HPLC) method was adopted,and the chromatographic conditions were as follows:(1) chromatographic column:TADE-PAK AF-C18 column(250 mm×4.6 mm,5 μm;(2) mobile phase:acetonitrile-methanol-0.5% ammonium acetate solution (Volume ratio 61∶18∶21);(3) flow rate:1 mL/min；(4) detection wavelength:210 nm;(5) column temperature:35 ℃;(6) sample size:10  μL.The results showed that the separation degree of oleanolic acid and ursolic acid was 1.73,which met the requirements.The linear relationship between ursolic acid and oleanolic acid was good in the range of 0.497 6～9.952 μg and 0.126 1～2.523 μg (r=0.999 9),respectively，The average recoveries of ursolic acid and oleanolic acid were 99.93% and 98.97%,respectively.The contents of ursolic acid and oleanolic acid in Paulownia leaves in Xiangxi were 4.54～7.07 mg/g and 2.50～3.20 mg/g,respectively.HPLC method has good separation effect,high sensitivity and high accuracy,and is a scientific and effective method for the determination of ursolic acid and oleanolic acid in Paulownia leaves.

Key words: HPLC, paulownia leaves, ursolic acid, oleanolic acid