The invention belongs to the technical field of tobacco, and particularly discloses a method for determining the content of acetic acid in triacetin for the tobacco. The method comprises the following steps: using methyl tert-butyl ether for diluting and extracting the acetic acid in the triacetin, adding an internal standard solution with definite concentration, performing gas chromatography-mass spectrometry analysis, and determining the amount in an internal standard method. The method disclosed by the invention overcomes the defects of sample processing and the determination method in the prior art, and optimizes the pretreatment method of samples and the detection conditions of an instrument; compared with the prior art, the method has the following excellent effects: the operation of the method is simple, convenient and accurate, the sensitivity and the precision are high, and the repeatability is good.