A liquid chromatography-tandem mass spectrometric（LC-MS/MS） method was developed for the determination of dimethyl yellow and diethyl yellow in dried bean curd，chili sauce，tofuru，dried beancurd sticks and biscuit.In this study，based on the chemical structures of dimethyl yellow and diethyl yellow，the sample was first extracted using acetonitrile solution，and the extract was then acidified and purified with a Bond Elut Plexa PCX cation anion exchange cartridge.After drying and re dissolvation，the analytes were separated by reverse phase LC using a C18 column,followed by detection using triple quadrupole mass spectrometry with positive electrospray ionization in multiple reaction monitoring（MRM） mode.The limits of quantitation were both 0.50 μg/kg.The recoveries of dimethyl yellow and diethyl yellow in food samples at three spiked levels of 0.50，5.0，80 μg/kg were in the range of 76.1%-93.0% with relative standard deviations（RSDs） of 1.7%-7.4%.The method could meet the requirement for rapid screening and quantitative analysis of dimethyl yellow and diethyl yellow in foods.