Objective: To identify Donglingcao tablets from different manufacturers by infrared spectroscopy. Method: The infrared spectroscopy of different manufacturers were analyzed by the original spectra; first derivative and second derivative.And it is clustered by calculating the distance between the spectra. Result: The original spectrum of same manufacturers is very simliar

and the similarities of different manufacturers are relatively small. In the second derivative spectrum

the main difference is the N-H stretching vibration absorption at 3 563 cm-1

C-O stretching vibration absorption at 1 158

1 117

1 080

1 037 cm-1 and C=C outside the plane bending vibration absorption at 983

862

680

655 cm-1. The intensity

shape and position of absorption peaks were obviously difference in all those places. The samples of different manufacturers were identified using clustering analysis. Conclusion: Using the infrared spectrum of the second derivative and clustering analysis can be successful in the identification of four manufacturers of Donglingcao tablets. This method is rapid

nondestructive

green and intuitive features.