In this research Photo-electrochemical etching processwas used to preparenano porous silicon from n-type Si.The characteristics of Silvered porous silicon samples(active-substrate), were studied as substrates in terms of surface-enhanced Raman scattering (SERS) phenomena. Maximum of (SERS) enhancement forCresylviolet (CV) dye was obtained. The active substrate was prepared by the immersion plating from the water solutionof AgNO3 with the (10-2M) concentration during (5min). The relation between the etching parameters, morphology of porous silicon surface and its SERS efficiency after silver deposition is examined .We show that thenano (PSi) allows the formation of a film with close-packed silver nanocrystals, which possess strong surface enhancement properties.