Abstract: To analysis and determinate the construction of flavonids in the leaves of raspberry as a new flavonids resource, the utility of high performance liquid chromatograph in combined with photodiode array detection and mass spectrometer technology (HPLC-PDA-MSⁿ) was successfully applied to simultaneous separate and determinate 15 flavonoides in ethanol extracts of leaves of Rubus idaeus. It was analyzed that constructions of flavonoid aglycones, the types of glycogen, sequences of polysaccharide using the information of molecular weight and ion fragmentations of MSⁿ provided by ion trap. In addition to liquid chromatography retention time, standard materials and published reports, the possible construction of 15 flavonoids in ethanol extracts was inferred. The result shows that it contains 8 quercetin derivatives and 7 kaempferol derivatives, which was corresponded with the published reports.