The features of the surface polaritons propagation are studied at the interface of an enhanced isotropic dielectric and a nanocomposite media with spherical metal inclusions. For each media, the frequency dependences of the propagation constant and the wave vector transverse components, group velocity and path length, penetration depth and longitudinal energy flow have been obtained and represented by diagrams. A significant impact of the imaginary part of dielectric permittivity on the wave characteristics of surface polaritons has been shown. (C) 2015 Elsevier B.V. All rights reserved.