Abstract: OBJECTIVE To establish an enzyme-linked immunosorbent assay(ELISA) method for the determination of Astragaloside Ⅳ(AST). METHODS Based on the preparation of monoclonal antibody against AST, an indirect competitive enzyme immunoassay method which could detect the content of AST in Radix Astragali was established by selecting the optimum working concentration. RESULTS The calibration curves were linear within the range of 39-1 830 ng·mL^-1. The average recovery(n=6) was 102.7%, and the relative standard deviations(RSD) of measurements in the intra-assay and in the inter-assay were ≤ 10%. The analysis result of ELISA method was consistent with that of HPLC test in AST determination of Radix Astragali. CONCLUSION ELISA method for the determination of AST is well established and can be applied to the quality control for Radix Astragali and its products.