This study analyzes the influence of soil-structure interaction on the seismic response of a three-dimensional (3-D) rigid foundation on the surface of viscoelastic soil limited by bedrock. Vibrations result only from P, SV, SH, and R harmonic seismic waves. The key step is the characterization of the soil-foundation interaction with the impedance matrix on one hand and the input motion matrix on the other hand. The mathematical approach is based on the method of integral equations in the frequency domain using the formalism of Green’s functions (Kausel and Peck, 1982) for layered soil. This approach has been applied to analyze the effect of soil-structure interaction on the seismic response of the foundation as a function of the kind of incident wave, the angles of wave incidence, the wave frequency and the embedding of foundation.