Objective: To assign phenolic acids and determine the content of chlorogenic acid contained in Fructus Xanthii collected from different product areas

and establish a practical quality control method for the herbal drug. Method: Major phenolic acids of this herb were identified based on their UV absorption

retention time and mass fragmentation characteristics. The content of chlorogenic acid was determined using ultra-performance liquid chromatography-ultraviolet detector(UPLC-UV). The mobile phase consists of 0.1% phosphoric acid in water as solvent A and methanol as solvent B. The detection wavelength is set at 327 nm and the column temperature at 35 ℃. The mobile phase flow rate is 0.4 mL·min-1. Result: A total of 9 major chromatographic peaks were assigned as phenolic acids

and peak area vs. content of chlorogenic acid showed a good linearity in the range of 3.5-350 mg·L-1 with a correlation coefficient of 0.999 9 and the average recovery was 101.7%. Conclusion: The established method is suitable for determining the content of chlorogenic acid contained in Fructus Xanthii and can be used to effectively control the quality of the herb;and assigning major characteristic peaks can significantly enhance specificity and accuracy in accessing the quality of herb.