HPLC was used in simultaneous determination of 2, 3, 5, 4'-tetera-hydroxystilbene-2-O-β-D-glucoside, emodin and physcion in Runzaozhiyang Capsules to preferably control and reflect the quality of Runzaozhiyang Capsules. The results showed that the calibration curves of 2, 3, 5, 4'-tetera-hydroxystilbene-2-O-β-D-glucosid, emodin and physcion was in good linearity over the ranges of 0.42016 ∼ 4.2016 μg/g (r=0.9999), 0.02912 ∼ 0.2912 μg/g (r= 0.9997), 0.011664 ∼ 0.11664 μg/g (r= 0.9997) and the average recovery rate was 98.30% (RSD = 1.68%), 97.84% (RSD = 2.11%), 98.26% (RSD= 1.89%) resp. Therefore the method is simple, feasible and reproducible.