PURPOSE: To improve the workability of the assembly of a shielding board and a substrate by a method therein a process in which metal pieces for supporting the rear of the substrate are folded toward the inside of the substrate is eliminated.

CONSTITUTION: In order to assemble a substrate 3 and a shielding case 1 together, springy metal pieces 1a which support the rear of the substrate 3 are provided by cutting the shielding case 1. Further, an inserting plate 2a which is inserted into the slit 3a of the substrate 3 and substrate stoppers 2b which are pressed against the surface of the substrate 3 when the substrate 3 and the shielding case 1 are assembled together are provided.