Objective? To establish a method for the determination of bromonitrile residue in crops. Method? Acetonitrile was used as extraction solvent, and the extraction solution was purified by dispersed solid phase extraction. The bromonitrile in the sample was reduced with metal zinc in acetic acid ethanol solution to form 2-methylene-glutaronitrile. The residual bromonitrile in the sample was obtained by measuring the content of 2-methylene-glutaronitrile. It was separated by DB-608 column, determined by gas chromatography tandem mass spectrometry (GC-MS/MS) multi-reaction monitoring (MRM) mode, and quantified by external standard method. Spinach, brown rice and tea were selected as the representative substrates. Results? There was a good linear relationship between the peak area of brominonitrile transformation products and the mass concentration in the range of 0.01-1mg/L. The lowest detected concentrations of brominonitrile in spinach, brown rice and tea were 0.01 mgkg, 0.02 mgkg and 0.05mgkg, respectively. The method has the advantages of easy availability of raw materials, mild conditions, simple operation, accurate quantification and good reproducibility, and can be used for the determination of bromonitrile residue in spinach, brown rice and tea were 0.01 mg/kg, 0.02 mg/kg and 0.05mg/kg, respectively. Conclusion? The method has the advantages of easy availability of raw materials, mild conditions, simple operation, accurate quantification and good reproducibility, and can be used for the determination of bromonitrile residue in spinach, brown rice and tea.