Abstract: RP-HPLC was applied to the determination of hesperidin and naringin in a prepared traditional Chinese medicine named “Chill Cough granules”.The SHIMADZU VP-ODS column (4.6 mm×150 mm,5 μm) was used as stationary phase,and a mixture of acetonitrile and H3PO4 solution (adjusted to pH 3.5 preliminarily),mixed in the ratio of 22 to 78 by volume,was used as mobile phase with a flow-rate of 1.2 mL·min-1.UV-detection at the wavelength of 283 nm was adopted in the determination.Good separation of the components determined from other co-existing constituents was attained,giving the value of R larger than 1.5.Linear relationships between values of peak area and mass concentration of hesperidin and naringin were obtained in the ranges of 2.8 to 56.0 mg·L-1 and 0.43 to 8.6 mg·L-1 respectively.Results of recovery and precision found were: average recovery of 99.2% for hesperidin and 98.7% for naringin with values of RSD′s (n=5) 1.2% and 2.1% respectively.