Abstract: A method of gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for determination of 34 kinds of organochlorine pesticides (OCPs), 12 kinds of polychlorinated biphenyls (PCBs) and 6 kinds of polycyclic aromatic hydrocarbons (PAHs) in soybean oil．Firstly, 1 g soybean oil and 3 g purified water were emulsified with surfactant, then extracted with 5 mL acetonitrile-xylene mixture (9∶1, V/V) by QuEChERS method, and detected by GC-MS/MS. The optimal experiments of adding surfactants about species and concentrations showed that the adding of surfactants can significantly increase the extraction efficiency of OCPs, PCBs, PAHs in soybean oil, and the appropriate surfactant is Tween 60. The calibration curves show a good linearity for all the congeners, and the relative coefficient is 0.993 8-0.999 7. The relative standard deviations (RSDs) are in the range of 1.59%-20.50%, and the spiked recoveries of OCPs range from 64.35% to 120.63%, that of PCBs are in the range of 49.65%-97.76%, and PAHs range from 74.05% to 101.52%. The developed analytical method is quick and easy maneuverability with satisfactory effect on the removing of oil, which is suitable for the determination of OCPs, PCBs, PAHs in soybean oil.