Objective To establish a method for the determination of cichoric acid, an active component in commercial extracts of Echinacea purpurea, by HPLC-PDA. and provide reference for the further use of Echinacea purpurea extracts. Method The samples were analyzed by HPLC-PDA on a C18 column with a PDA at 330 nm and the temperature at 35 ℃. The mobile phase was a mixture of acetonitrile and 0.1% phosphoric acid at a flow rate of 1.5 mL/min. Results The standard curve was linear in the cichoric acid concentration range of 0.456~2.28 μg (r=0.9996). The average recovery was 98.18% (RSD=1.12%). Conclusion The method was rapid, sensitive and had good reproducibility, which could be used for quality assessment of cichoric acid in commercial extracts of Echinacea purpurea.