G-Fe3O4 magnetic composite materials with excellent adsorption properties were successfully synthesized by solvothermal method,and then applied in magnetic solid phase extraction(MSPE) process for 9 common pesticides in peanut samples.The extraction conditions were optimized,such as dilution ratio of sample extract,amount of magnetic composite materials,extraction time,type and dosage of elution solvent.Coupled with gas chromatography-tandem mass spectrometry(GC-MS/MS),a novel multi-residue analytical method was established for these nine pesticides in complex peanut matrix.The results showed that the limits of detection for nine pesticides ranged from 0.07μg/kg to 1.85μg/kg,the linear ranges were 0.23-1000μg/kg,and the correlation coefficients(r2) were not less than 0.994.The average recoveries at three spiked levels ranged from 81.9% to 119.3%,with relative standard deviations(RSD) of 2.1%-6.6%.With the advantages of simple operation,high recovery,good stability and low cost,this method was a rapid,efficient and accurate technique for multi-residue determination of pesticide,especially in high fatty matrix such as peanut sample.