A sensitive method for the simultaneous determination of 21 phthalate acid esters(PAEs) in foods by gas chromatography-mass spectrometry(GC-MS) was firstly proposed.Different separation and purification methods were selected according to the types of food,and the chromatographic conditions were optimized.Qualitative detection and confirmation were acquired by the extraction of characteristic ions,and the interferences due to the complex matrixes were effectively eliminated,thus avoiding the possibility of false positive results.The mass spectrometric fragmentation rule of PAEs was also discussed in detail.The calibration curves of 21 compounds were linear in the range of 0.1-100 mg/L with correlation coefficients not less than 0.999 2.The quantitative limits(LOQs,S/N=10) ranged from 0.05 mg/kg to 0.5 mg/kg.The average spiked recoveries were in the range of 83%-106% at spiked levels of 0.10-10 mg/kg with relative standard deviations(RSDs,n=6)of 2.9%-5.5%.The method was successfully applied in the investigation of the PAEs distribution in foods and food packaging material of South China area,and the source of PAEs was also discussed in detail.