An oxidized graphene based magnetic nanoparticles(GO-Fe3O4) was synthesized by one step,and used as the adsorbent for the magnetic solid-phase extraction(MSPE) of six triazine herbicides in environmental water samples prior to high performance liquid chromatography with mass spectrometry(HPLC-MS/MS).The synthesized material was characterized by scanning electron microscopy(SEM) and Fourier transform infrared spectrometry(FTIR).Various experimental parameters including amount of GO-Fe3O4，extraction time， pH values and ionic strength of sample solution and desorption conditions were optimized to improve the extraction efficiency. The limits of detection of the method ranged from 0.1 ng/L to 1.0ng/L,and the enrichment ranged from 616 to 902 for six triazine herbicides. The method was applied in the analysis of actual water samples from Taihu lake，canal and moat in Suzhou，with spiked recoveries of 85.4%-117.6% and relative standard deviations(RSDs) of 1.2%-10.0%.Attributed to its simplicity and rapid operation，high enrichment and low detection limit，this method could be used to analyze the trace residues of triazine herbicides in water samples.