Abstract: To establish a QAMS methodology for simultaneous determination of quercetin and kaempferol contents in Crotalaria ferruginea, HPLC was applied on a C₁₈ column (4.6 mm×250 mm, 5 μm) with acetonitrile:0.4% CH₃COOH (40:60) for the mobile phase. The column temperature was kept at 30℃ and flow rate at 1.0 mL·min^-1. The eluate was detected at the wavelength of 360 nm. Quercetin was used as the internal standard to establish the relative correction factor (RCF) for the quantitative analysis of multi-components on QAMS. The RCF of kaempferol was calculated. The contents of the two compounds were measured by both the external standard method and QAMS to verify the validity of the proposed QAMS methodology. The resulting RCF showed good durability on both quercetin and kaempferol determinations. There were no significant differences between the data obtained by QAMS and by the external standard method. Consequently, this new approach was considered simple, rapid and applicable for quality control on raw material and processed products involving C. ferruginea.