The classical model on erosion combustion of energetic materials explains the phenomenon of increasing the combustion rate with growing an external hot flow speed only by heat effects caused by turbulence of the flow. However, experiments with flammable materials show that combustion in high-speed and high-enthalpy hows is accompanied with mechanical erosion, i.e., with dispersing the surface particles. In the present paper a new model of erosion combustion is suggested that describes an influence not only of turbulence but also of mechanical destruction (dispersing) of the material on the combustion rate of energetic materials. The experiments conducted for combustion of polysiloxane rubbers in high-enthalpy flows showed a good agreement of theoretical and experimental results.