PURPOSE: To produce a molding having good electromagnetic wave-shielding performance by mixing a small quantity of an electrically conductive material, by dispersing carbon fiber pieces in ultra-high-molecular-weight PE powder while heating said PE powder in an inert atmosphere at a temp. lower than the m.p. of the PE while stirring at a high speed.

CONSTITUTION: 10W50pts.wt. carbon fiber pieces (e.g. one having a diameter of 5W9 de and a length of 10μ to 5mm) are dispersed in 100pts.wt. ultra-high-molecular-weight PE powder having an MW of 1,000,000 or above, while heating said PE powder in an inert atmosphere at a temp. (10W40°C) lower than the m.p. of the PE while stirring at a high speed. Most of the carbon fiber pieces are dispersed while they are in contact with one another, so that a molding having good electromagnetic wave-shielding performance can be obtd. by mixing the electrically conductive material in a quantity less than that in conventional molding.