A gas chromatography（GC）-mass spectrometric（MS） method coupled with headspace solid phase microextraction（HS-SPME/GC-MS） was established to analyze 13 benzene series（BTEX） in seawater.The seawater samples were extracted by 100 μm polydimethylsiloxane（PDMS） fiber,and determined by GC-MS under selective ion mass mode with the external standard method.Several factors affecting the extraction efficiencies were optimized,including type of fiber,extraction temperature,extraction time,desorption time and sample volume.Under the optimized conditions,the linear equations were obtained in the concentration range of 0.16-32 μg/L with correlation coefficient（r） of 0.999 0-1.000 0.The limits of detection（S/N=3） were in the ranges of 0.006-0.043 μg/L.The recoveries at three spiked levels of 0.16,1.6,16 μg/L ranged from 80.0% to 117% with relative standard deviations（RSD,n=6） of 2.0%-5.6%.The proposed method was simple,sensitive,rapid and green,and was suitable for the determination of 13 BTEX in seawater.