Using the discrete dipole approximation, we analyze surface plasmon resonance (SPR) in the core(Au)/interlayer/shell(Ag) nanoparticles. Here, the role of the Au core is typically central. We focus on the effect of the interlayer properties on SPR. If the interlayer is metallic, the contribution of the Au core to SPR is found to be suppressed, while the semiconductor interlayer can enhance this contribution. The porous Si interlayer exhibits the combined features inherent to a cavity and amorphous Si. These conclusions are illustrated by showing the distribution of electric field in and near nanoparticles. (C) 2014 Elsevier B.V. All rights reserved.