OBJECTIVE： To establish a method for the simultaneous determination of caffeic acid， isoschaftoside and schaftoside in Xiaoyan lidan tablet. METHODS： RP-HPLC was performed on the column of Phenomenex C18 with mobile phase of methanol - 0.1％ phsphate acid （gradient elution） at flow rate of 0.8 ml/min， the detection wavelength was 334 nm， column temperature was 25 ℃， and the injection volume was 10 μl. RESULTS： The linear range was 0.10-2.81 μg for caffeic acid（r＝0.999 9）， 0.20-5.63 μg for isoschaftoside （r＝0.999 9） and 0.10-2.63 μg for schaftoside（r＝0.999 9）；RSDs of precision，stability and reproducibility tests were lower than 3％； recoveries were 96.3％-100.4％（RSD＝1.59％，n＝9）， 97.3％-101.2％ （RSD＝1.28％，n＝9） and 96.6％-100.6％（RSD＝1.39％，n＝9）， respectively. CONCLUSIONS： The method is sensitive， accurate， reliable and reproducible， and can be used for the simultaneous determination of caffeic acid， isoschaftoside and schaftoside in Xiaoyan lidan tablet the quality control of Xiaoyan lidan tablet.