High-d. polyethylene was blended with comp. maleic anhydride-grafted polyethylene and ground tire rubber (40:10;50 by mass) in a co-rotating twin screw extruder at 180 degrees C and studied for static and dynamic mech. properties, processing parameters, thermal anal. and morphol. The addn. of grafted polyethylene resulted in decreasing the mass flow and abrasivity of the blends and in increasing their tensile strength and elongation at break because of improving the compatibility of the blend components.