Purpose: The total flavonoids content was determined by the colorimetric method of NaNO₂-Al(NO₃)₃, and the changes of the contents of five kinds of flavonoids were detected by the high performance liquid chromatography (HPLC) to study on the content of flavonoids in the brewing process of the different processing of the semen astragali complanati, which provided an important reference for the brewing and quality control. Results: The contents of other flavonoids in semen A complanati showed a increase trend in the beginning, then followed by a decrease, which was consistent with the changing trend of total flavonoids. Compared with the untreated group, all the contents of flavonoids in the treated group were higher in the brewing process except myricitrin. Conclusion: The flavonoids content could be improved by soaking and germination of semen A. complanati before brewing.