A method based on gas chromatography-triple quadrupole mass spectrometry with headspace（HS/GC-MS/MS） was developed for the determination of three xylene isomers in seafoods.The samples were incubated at 90 ℃ and oscillated for 40 min,then separated on an HP-INNOWax column.The determination of the target compounds were performed by GC-MS/MS under the multiple reaction monitoring（MRM） mode,and the quantification was carried out using the external standard method.The calibration curves for three xylene isomers were linear in the range of 50-1000 μg/kg with their correlation coefficients（r2） larger than 099.The limits of detection（LOD） and quantitation（LOQ） of the method were 25 μg/kg and 50 μg/kg,respectively.The recoveries at three spiked level of 60,150,500 μg/kg were in the range of 896%-1124% with relative standard deviations（RSD） not more than 115%.The method was successfully applied in the determination of xylene isomers in seafoods.With the advantages of simple operation,accuracy and high sensitivity,the method was suitable for the determination of xylene residues in seafoods.