PRINTED BOARD

PURPOSE:To provide a shielding effect to electromagnetic influence from an exterior and/or to the exterior by covering both sides with printed patterns, and electrically sufficiently connecting them with first, second ground patterns via through holes to ground them. CONSTITUTION:A solder resist 3 is laminated on a printed pattern 2 formed with an electric circuit on one side surface of a board 1, and a first metal foil 5a of a conductive copper foil is formed on an insulator 4 for insulating the pattern 2. A second metal foil 56 of a conductive copper foil is formed on the opposite surface of the board 1. First, second ground patterns electrically in contact with or connected to as many points as possible with the foil 5a are formed at part or several positions on the periphery or inside the foils 5a, 5b, and connected with ground patterns 6a, 6b via through holes. Accordingly, a grounded shielding structure can be obtained to shield against electromagnetic influence from and to outside.