This paper considers the effect of surface modification of active filler, namely, carbon black on the mechanical properties of rubber compounds in manufacturing highly-filled elastomeric materials. It was found experimentally that the process of filler modification results in material softening, not influencing its strength. The model is proposed which is capable of describing a change in the behavior of rubber compounds caused by filler surface modification. Application of the modified filler reduces the hysteresis losses of vulcanizates and looks promising for manufacturing tires.