A pesticide residue detection method, comprising the steps: (o) measuring, in the field of detecting the pesticide residue in a sample of a food system, the Raman spectra of reference samples of a plurality of different food systems containing pesticides of known compositions and different concentrations to obtain reference Raman spectra, and thereby establishing a reference Raman spectrum library, the reference Raman spectrum library including reference Raman spectra for different food systems containing pesticide residues of known compositions and different concentrations; (a) irradiating the sample of the food system to be detected by an exciting light and collecting a Raman scattered light from the sample; (b) acquiring a Raman spectrum of the sample of the food system from the collected Raman scattered light; and (c) comparing the Raman spectrum of the sample of the food system with reference Raman spectra of a sample of the same food system for known pesticides in the reference Raman spectrum library to determine composition and concentration of pesticide residue in the sample of the food system, wherein the step (c) comprises: extracting a peak position of a characterizing peak from the Raman spectrum of the sample of the food system to be detected and comparing it with reference Raman spectra of a sample of the same food system in the reference Raman spectrum library to determine whether the sample to be detected contains a certain pesticide residue or not; and if it is determined that the sample to be detected contains the pesticide residue, extracting a peak intensity or peak area of the characterizing peak of the Raman spectrum of the sample of the food system to be detected and comparing it with the reference Raman spectra of the same food system, and thereby determining the concentration of the pesticide residue in the sample of the food system to be detected. (o) measuring, in the field of detecting the pesticide residue in a sample of a food system, the Raman spectra of reference samples of a plurality of different food systems containing pesticides of known compositions and different concentrations to obtain reference Raman spectra, and thereby establishing a reference Raman spectrum library, the reference Raman spectrum library including reference Raman spectra for different food systems containing pesticide residues of known compositions and different concentrations; (a) irradiating the sample of the food system to be detected by an exciting light and collecting a Raman scattered light from the sample; (b) acquiring a Raman spectrum of the sample of the food system from the collected Raman scattered light; and (c) comparing the Raman spectrum of the sample of the food system with reference Raman spectra of a sample of the same food system for known pesticides in the reference Raman spectrum library to determine composition and concentration of pesticide residue in the sample of the food system, extracting a peak position of a characterizing peak from the Raman spectrum of the sample of the food system to be detected and comparing it with reference Raman spectra of a sample of the same food system in the reference Raman spectrum library to determine whether the sample to be detected contains a certain pesticide residue or not; and if it is determined that the sample to be detected contains the pesticide residue, extracting a peak intensity or peak area of the characterizing peak of the Raman spectrum of the sample of the food system to be detected and comparing it with the reference Raman spectra of the same food system, and thereby determining the concentration of the pesticide residue in the sample of the food system to be detected.