Abstract: AIM: To establish a reliable method for quantitative analysis of scutellarin. METHODS: A triple-quadrupole tandem mass spectrometer was used as a detector for HPLC to determine scutellarin. As to MS/MS, multi-reactions monitoring (MRM) scan mode was employed. Among the product ions of scutellarin, m/z -285 is the most abundant in intensity, thus the parent-daughter ion pair of m/z -461 and m/z -285 was selected as MRM ions pair. MS/MS conditions were optimized to achieve highest sensitivity. The mobile phase of HPLC was 100% methanol and the analytical column was Beckman ODS-1. The flow rate of HPLC was 0.9 mL.min^-1. The areas of ion flow peaks were used to determine the quantity of scutellarin. To give an example of its applications, this method was used to determine the amount of scutellarin in Erigaron breviseapus extract. RESULTS: The amount of scutellarin accounted for 6.98%±0.11% in Erigaron breviseapus extract. The standard curve for scutellarin showed good linearity over the concentration range of 20～160 ng.mL^-1 (γ=0.999); the recoveries of scutellarin at added amount of 20, 60 and 160 ng are 96.5%, 97.4% and 97.3% respectively; the limit of detection is 1ng, and the analysis time of each sample was 4 minutes. CONCLUSION: This method is highly sensitive, fast, and very accurate. Therefore, it is possible to be applied to study the metabolism of scutellarin.