Abstract: A method for the determination of benzoapyrene in deep frying oil was developed by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Samples were extracted with acetonitrile and purified by EMR-Lipid SPE column. The separation of benzoapyrene was carried out on a RRHD SB-C₁₈ column with gradient elution of acetonitrile and water. An atmospheric pressure chemical ionization (APCI) interface was used as the ion source and the analysis was performed in the multiple reaction monitoring (MRM) mode, the samples were quantified by isotope dilution mass spectrometry (IDMS) with benzoapyrene-d₁₂ as internal standard. The results of method showed the linearity in the range of 1~200 μg/kg, R²=0.9997.The limit of detection (LOD) was 0.2 μg/kg and the limits of quantification (LOQ) was 0.6 μg/kg. The average recovery ranged from 94.0% to 98.7% with the relative standard deviation (RSD) range of 2.1%~5.6%. Benzoapyrene was detected in the 20 samples, and the content was 1.76~6.81 μg/kg. The results suggested the method was suitable for the detection of benzoapyrene in deep frying oil, for its obvious advantages such as simpler pretreatment, higher accuracy and sensitivity.