PURPOSE: To produce a lightweight decorative panel by performing decorative working on the surface or the front and the back of a ligneous board to form the ligneous board having the decorative layers and thereafter forming many holes on both side parts from the sides to the central direction and then performing decorative working on the side parts.

CONSTITUTION: Docorative layers 3 are formed by performing decorative working on the surface or the front and the back of a ligneous board 2. Many circular holes 4 are formed on both side parts 5 of the ligneous board 2 from the sides toward the central part by a boring machine or the like. Diameter of the holes 4 is regulated to a range within (1/4-4/5) of thickness of the ligneous board 2. Therefore weight saving is sufficiently performed and also strength is held. Thereafter the side decorative material is fixed in grooves 7 and fitted to both side parts 5 and the side decorative layers 6 are formed. Accordingly a lightweight decorative panel 1 having strength equal to the conventional decorative panel 1 is produced.