A method was developed for the identification of chemical constituents in Bufei Yishen formula by UPLC-Q-Orbitrap MS with Mass Frontier analysis software.The sample was separated on a Phenomenex kinetex C18 column(100 mm×2.1 mm,2.6 μm) by gradient elution with 1‰ formic acid-acetonitrile as mobile phase at a flow rate of 0.2 mL·min-1,a column temperature of 25 ℃ and an injection volume of 5 μL.Total of 242 chemical components in Bufei Yishen formula were confirmed by using Mass Frontier 60 workstation to match the collected fragment ions,combined with the literature report,in which 205 chemical components were confirmed in positive ion mode,including 10 from Ginseng Radix Rhizoma,17 from Astragali Radix,28 from Paeoniae Rubra Radix,9 from Fritillariae Thunbergii Bulbus,63 from Perillae Fructus,9 from Citri Reticulatae Pericarpium,8 from Ardisiae Japonicae Herba,7 from Corni Fructus,26 from Schisandrae Chinensis Fructus and 28 from Epimedii Herba.While 37 chemical components were confirmed in negative ion mode,ie23 from Ginseng Radix Rhizoma and 14 from Astragali Radix.The proposed method is comprehensive and rapid in the identification of chemical components in Bufei Yishen formula,which provides the basic data to reveal its pharmacodynamics substances.