To simply provide a curved member of a resin molding which is beautiful in appearance and can correspond to various curvatures at low costs and its production method.

When a method including a process for preheating the lengthy resin molding incorporated with a wood flour and a process in which the preheated resin molding is passed between two lower supporting rolls arranged horizontally in parallel and upper holding rolls fitted in parallel above the supporting rolls to bend the molding is used, the molding can be bent appropriately. A hollow part is formed in the molding, and an insert such as a metallic core material is preferably fitted into the hollow part so that flexural stress can be dispersed uniformly and the molding can be bent homogeneously. After the bending, by annealing the molding, the return of bending can be reduced, and the molding having a larger curvature can be obtained.