Objective: To determine the quercetin content of Polygonum flaccidum from different growing areas. Method: The chromatographic column was Hypersil BDS C18(4.6 mm×250 mm

5 μm).The mobile phase was methanol-0.4%phosphoric acid (50: 50).The flow rate was 1 mL·min-1

the detection wavelength was at 365 nm. The column temperature was at room temperature.The sample volume was 20 μL. Result: The standard curve regression equation was A=73 185C-21.47(r=0.999 5).It showed a good linear relationship between 0.004-0.014 g·L-1

and average recovery was 99.29%

RSD 1.30%. Conclusion: The method is simple and reliable

could be used to control the quality of these medicinal materials.