An electronic instrument comprises a printed circuit substrate on which electrical parts are actually mounted, a frame placed on the front side of the printed circuit substrate and having openings at least at positions corresponding to the electrical parts, a front sheet disposed at a position opposed to the printed circuit substrate with the frame interposed therebetween and provided with an adhesion margin on the peripheral portion thereof, a back sheet disposed on the back side of the printed circuit substrate and provided with an adhesion margin on the peripheral portion thereof, and an adhesive agent applied to the adhesion margins of the front sheet and the back sheet to cause the printed circuit substrate and the frame to be sandwiched between the front sheet and the back sheet.