Surface-enhanced Raman spectroscopy (SERS) is a sensitive and specific analytical technology based on the fingerprint information of probe molecules (molecular vibration, rotation information, etc). With the help of precious metal nanomaterials with excellent plasma properties, SERS can be used for the analysis and detection of single-component or complex multi-component trace pesticide residues. Among them, flexible SERS substrate has the characteristics of high porosity, low preparation cost, flexibility, folding and bending, etc. It has incomparable advantages over rigid SERS substrates in the extraction, filtration and concentration of probe molecules in complex sample systems. Flexible SERS substrates are mainly based on biobased materials, polymer and carbon materials to support and fix the modified surface to provide spectral enhancement of precious metal nanomaterials. The common preparation methods and applications of these three types of flexible SERS substrates are reviewed. The latest research progress in the application of flexible SERS substrates to different pesticide residues is introduced by making full use of the advantages of fingerprint of SERS. Finally, the problems to be solved urgently for the development and application of SERS technology are put forward. © 2022, Editorial Office of FINE CHEMICALS. All right reserved.