To provide a method of manufacturing a gasket which has a high sealing performance and surely enables to prevent malfunctions of electronic equipments caused by external noise.

On the surface of one of a pair of conductive metal members which constitute an electronic equipment storing case, a liquid rubber material which is hardened by irradiation of active energy beams is attached. Then, the attached rubber material is irradiated with active energy beams to be hardened into a predetermined hardness. Next, the surface of the hardened rubber material is covered with a film formed of a conductive metal material extended to the surface of the other member. Consequently, the electrical continuity is established between the pair of members constituting the electronic equipment storing case, and a space between these members is electromagnetically sealed, thereby increasing the electromagnetic shielding effect of the electronic equipment storing case and preventing malfunctions of electronic equipments due to external noise.