A manufacturing method of composite wood that arbitrary amount of wood can be used, nailing is possible and a product with arbitrary configuration is easily manufactured is provided. A melted binder resin and a plurality of wood pieces are kneaded. Then, a resultant kneaded material of the wood pieces and the binder resin is strongly pressed. The binder resin is cooled while the kneaded material is strongly pressed. Alternatively, strong pressing and cooling are repeated for the kneaded material. As a result, the binder resin is cured. A resultant composite wood is cut into a board with a predetermined thickness or a bar with a predetermined dimension and assembled into a desired product. A water content of the wood pieces may be evaporated by heat from the binder resin or may be evaporated by heating the wood pieces. |