The invention belongs to the technical field of food safety detection, and in particular relates to a method for identifying vegetable oil and waste table oil by using SIFT / MS. The present invention measures furan, acrylamide, furfural, 2-pentylfuran, acrolein, exogenous pollutants citral, limonene, diallyl sulfide, m-cresol, 4-isopropyl Toluene, methyl piperonol, oxidative decomposition products: aldehydes such as heptanal, octanal, 2-heptenal, 3-hexenal, 2-octenal, (E, E)-2-decadienal , acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, other oxidative decomposition products such as acetone, butanone, 2-heptanone, 1,3-propylene glycol, 1,4-butyrolactone, propionate Esters 28 components, and then identify vegetable oil and waste cooking oil. The method not only saves the cost of reagents, but also has no pre-concentration, no column separation, no need for standard products, and has the advantages of high sensitivity, simplicity, speed, accuracy and the like.