Abstract: The paper established a method of the phthalates' determination in the different plastic packaging plant oil by Gas Chromatography- Mass Spectrometry. Using the different separation and purification methods to the different plastic packaging plant oil,this new method of gas chromatography- mass spectrometry optimized the separation conditions of edible vegetable oil.The results showed that the minimum detection limit to the phthalates was 0.01～0.05 mg / kg,the correlation coefficient was 0.9965～0.9990,and the recovery rate was 83.1% ～98.6%,and the RSD was 1.94% ～4.73%.The method was applied to the analysis of PAEs content in the plant oil.Compared with the GB / T 21911 standard method,it was showed that this method was simple in operation and the determination result was accurate.It could be used as a confirmatory method to the phthalates of plant oil.