Abstract: OBJECTIVE To establish HPLC fingerprint suitable for Lingnan characteristics decoction pieces processed Codonopsis Radix and its raw products, analyze and compare the changes of Codonopsis Radix before and after steaming, and lay a foundation for establishing quality control standard for processed Codonopsis Radix. METHODS Waters Symmtry C₁₈ reversed-phase column(250 mm×4.6 mm, 5 μm). The mobile phase was methanol-0.1% formic acid(gradient elution), column temperature was 30℃, flow rate was 1.0 mL·min^-1, detection wavelength was 283 nm, recording time was 55 min. The similarity evaluation system of traditional Chinese medicine fingerprint(2012 edition) was used for data processing. RESULTS The fingerprint similarities of different batches of processed Codonopsis Radix were between 0.750-0.979. Ten common characteristic peaks were selected according to the difference of raw and processed products. CONCLUSION The established method is stable and reproducible. The differences of fingerprints between raw and processed products of Codonopsis Radix provide a reference for the establishment of the quality control standard of processed Codonopsis Radix.