The three-layer structure of silver/graphene/silver (AG/GE/AG) was prepared by vacuum evaporation method and wet transfer method, and then through a high temperature annealing, a reusable AG/GE/AG composite structure substrate was obtained. The electric field distribution and theoretical enhancement factor were calculated using COMSOL Multiphysics simulation software. The Raman measurements show that the relative standard deviation (RSD) values of the D, G, and two-dimensional peaks of graphene are 26.0%, 17.8%, and 23.6%, respectively, indicating its good uniformity. The detection limits for rhodamine 6G (R6G) and crystal violet (CV) are as low as 10 ^-7 mol/L. Using R6G with a concentration of 10 ^-5 mol/L as the probe molecule and sodium borohydride solution as the cleaning agent, the repeatability experiment of AG/GE/AG substrate was studied. Taking Raman peaks at 613 cm ^-1and 773 cm ^-1 as examples, the Raman intensity was maintained at 71.08% and 71.60%, respectively.