A network structure surface-enhanced Raman scattering (SERS)-active substrate is fabricated by adding Ag sol dropwise on adhesive tape. Scanning electron microscope (SEM) is employed to characterize the structure of the as-prepared substrate. The substrate shows great SERS enhancement ability and good uniformity by using p-aminothiophenol (PATP) as probe molecules. The detection of crystal violet (CV) in aqueous solution is demonstrated, and the detection limit is as low as 10-12 M with the aid of the substrate. The results indicate that the proposed method is a potential approach for the fabrication of SERS substrates.