Optical properties of spherical metal-oxide nanoparticles are studied in the framework of the Drude theory. The frequency dependences of the real and imaginary parts of the dielectric constant, the coherence loss parameter and the absorption coefficient of two-layer Ag, Al, Cu nanoparticles with a radius of 10–30 nm in different matrices are calculated. It is found that the behavior of the frequency dependences of the imaginary part of the dielectric constant and the absorption coefficient in the low-frequency region is determined by the contribution of the electron surface scattering mechanisms.