The invention relates to a method for simultaneously determining vanillin, ethyl vanillin and coumarin in an electronic cigarette solution. The method is characterized by comprising the steps of accurately weighing a certain amount of electronic cigarette solution, carrying out vibration dilution by virtue of an organic solution containing internal standard substances, adding 1mL of solution to a 2mL chromatography bottle, and simultaneously and quantitatively analyzing the contents of vanillin, ethyl vanillin and coumarin in the cigarette solution by virtue of a gas chromatography-mass spectrum/selected ion monitoring mode (GC-MS/SIM). The method has the advantages that less sample amount and reagent amount are required, the operation is simple, rapid and efficient, the assay determination sensitivity is high, and the detection limits of vanillin, ethyl vanillin and coumarin respectively are 0.03(mu)g/mL, 0.04(mu)g/mL and 0.03(mu)g/mL, variable coefficients of determination results of vanillin, ethyl vanillin and coumarin respectively are 1.9%m 3.3% and 4.2%, the recovery rate is 96%-112%, the determination results are stable, the recovery rate is high, and the quantification is accurate.