Porous silicon-Au/Ag dendritic composites have gradually demonstrated their advantages as SERS substrates since the discovery of surface-enhanced raman scattering (SERS) in the 20th century. They have found widespread application in biology, chemistry, medical treatment, and other fields. The advantage of SERS substrate porous silicon, focusing on Ag/Au in preparing the porous silicon substrate method, was examined over recent years. The porous silicon substrate with a metal coating is cost-effective to fabricate and offers a high detecting capability. This paper illustrates the application in the morphology of dendritic structures under different conditions of preparation and detection. A short analysis carried out on the future evolution of the porous silicon-Ag/Au dendritic composite structure as a SERS substrate.