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Due to the advantages of strong specificity and high sensitivity, surface-enhanced Raman spectroscopy (SERS) has been widely used in the detection of trace compounds. SERS substrates used for detection had become a research highlight in recent years. However, researchers mostly focused on the reduction of limits of detection, and seldom considered the cost. Cellulose acetate membrane was prepared by using cheap corn straw. Then, coupled with gold nanoparticles, an SERS substrate with stable test performance and low limits of detection was prepared. The characterization of the SERS substrates showed that the gold nanoparticles formed regular multilayer structure on the surface of cellulose acetate, which was conducive to the formation of “hot spots” and increased the signal. Abundant pore structure and hydrophilicity of the SERS substrates made the enrichment test feasible. It also had a certain thermal stability, to ensure that a short time of laser irradiation would not burn the substrate. The SERS test results showed that the enrichment test had a lower limit of detection than the drop test. It can reach 10-7g/mL, and had a good linear relationship in the concentration range of 10-7~10-6g/mL. Applicability analysis showed that it had good detection effect on several kinds of water pollutants, and provided a technological process for preparing surface-enhanced Raman substrates from corn straw. Due to the cheap raw material and simple preparation process, the preparation cost of SERS substrates could be effectively reduced. Thus, it laid the application foundation for high value utilization of straw and rapid and high sensitivity detection of water pollutants.