Objective: To analyze the compatibility rationality between the raw material and auxiliary material sodium bisulfite in Zhengqin Fengtongning injection.Methods: HPLC was applied to detect the contents of the impurity and the main component in Zhengqing Fengtongning injection, and ion chromatography was applied to determine the content of sodium bisulfite in Zhengqing Fengtongning injection.The changes of impurity, main component and sodium bisulfite among the samples were compared before and after the stress testing (high temperature at 40℃, 60℃ and illumination at 4 500 lx).LC-MS-MS was used to identify the structures of the impurities.Results: The impurity in Zhengqing Fengtongning injection was the combination of the raw material and sodium bisulfite.Conclusion: It is irrational for Zhengqing Fengtongning injection to use sodium bisulfite as the antioxidant.