Objective: To establish a HPLC method for simultaneous determination of vanillic acid and protocatechuic acid in Capparis spinosa. Method: The samples were separated on a C18 column (4.6 mm×150 mm

5 μm)

the mobile phase was consisted of methanol-0.1% phosphoric acid with gradient elution at the flow rate of 0.8 mL·min-1 and the detection wavelength was set at 258 nm. Result: The calibration curves for vanillic acid and protocatechuic acid were linear in the range of 0.001 50-0.009 00

0.005 80-0.034 8 μg respectively. All the correlation coefficient were 0.999 9

and the average recoveries (n=3) were 105% and 103% with corresponding RSDs of 1.90% and 1.81% respectively. Conclusion: The method is simple

accurate and sensitive and can be used to determine the content of the vanillic acid and protocatechuic acid in C. spinosa.