Objective: To establish a quantitative determination method of HPLC for two polymethoxylated flavonoids in Bauhinia championii. Method: The determination was performed on a DIKMA Platisil ODS column (4.6 mm×250 mm

5 μm) with acetonitrile-0.1% phosphoric acid as the mobile phase by gradint elution (0 min

25%A; 15 min

45%A; 40 min

50%A). The flow rate was 0.8 mL·min-1 and the detection wavelength was set at 324 nm. Result: The calibration curves were linear in the range of 0.008 4-0.336 0 μg (for 5

7

3'

4'

5'-pentamethoxy flavone

r=0.999 9)

0.013 4-0.536 0 μg (for 3'

4'-methylenedioxy-5'

5

6

7-tetramethoxyflavone

r=0.999 7). The average recoveries were 99.41% (RSD 0.57%) and 98.65% (RSD 1.01%) respectively. Conclusion: This method is simple and accuracy with good separation and reproducibility. It can be used as the quality control of the polymethoxylated flavonoids in Bauhinia championii.