A novel method was developed for the simultaneous determination of three trace non-volatile impurities，capsaicin，dihydrocapsaicin and piperine in gutter oils using liquid chromatography-tandem mass spectrometry(LC-MS/MS).Analytes were extracted with hexane saturated acetonitrile，then separated on a Thermo BDS Hypersil C18 column(100 mm×2.1 mm，2.4 μm)by gradient elution.The qualitative and quantitative analysis of target compounds were carried out by electrospray ionization mass spectrometry under the positive mode with multiple reaction monitoring(MRM).The correlation coefficients of three calibration curves were over 0.99 in the corresponding concentration range.The average recoveries of three analytes varied from 65% to 89%，with relative standard deviations(RSDs) of 5.3%-16.1%.The limits of detection(LOD，S/N≥3) and quantitation(LOQ，S/N≥10) were 0.03 μg/kg and 0.1 μg/kg，respectively.The results of the real sample tests showed that this method is simple，rapid，sensitive and reliable，and could be used as one of the identification means for gutter oils.