A reversed phase (RP)-HPLC method was established for simultaneous determination of chlorogenic acid, arctiin and forsythin in Yinqiao Jiedu Granules, which was a commonly used Chinese herbal medical preparation for treatment of rheum ailments. The determination was based on a gradient elution (A: 1% acetic acid, pH=3.0, B: methanol) on a C18 column and an automatic wavelength switching program, where 325 nm was used for chlorogenic acid and 280 nm for arctiin and forsythin, respectively. Good linearities were obtained over the range of 2-200 mg.l(-1) for the 3 objective compounds. The spike recoveries were within 96.0-97.9%.