PURPOSE: To form a synthetic wooden board with lesser warping and distortion by a method in which cellulosic short fibers are temporarily pressed for molding and then bonded with a decorating material.

CONSTITUTION: Wood chips, pulp, etc., are dried, impregnated with a resin liquid, dried, and then broken to obtain an aggregate 1. A base material formed by mixing the aggregate 1 and fibers 2 or the base material with a net cloth 3 is temporarily hot- or cold-pressed to cause the integral adherence of the aggregate 1 and the entanglement of the fibers 2 and the net cloth 3. A decorating material 4 (e.g., plywood, Victoria lawn, etc.) is then bonded to the surface of the molding so obtained without the aid of any adhesive means and pressed for molding to form a synthetic wooden board free of warping and distortion.