Objective: To establish an HPLC method for the determination of codonoposide in Codonopsis lanceolata Benth. et Hook.F..Methods:The HPLC analysis was performed on a Kromasil C18column (250 mm×4.6 mm,5 μm). The mobile phase was 0. 1% phosphoric acid-acetonitrile (70∶ 30) and the flow rate was 1. 0 ml·min-1 . The detection wavelength was 203 nm and the column temperature was 30℃. Results:Codonoposide in Codonopsis lanceolata Benth. et Hook. F. had a good separation from the oth-er components, and a good linear relationship was obtained within the range of 1. 09-17. 41 μg( r=0. 999 9). The average recovery was 98. 46%(RSD=1. 64%, n=6). Conclusion: The method is practicable with promising repeatability, which can be applied in the content determination of codonoposide in Codonopsis lanceolata Benth. et Hook. F. .