<p>A shielding structure comprises a printed circuit board on which electronic parts are mounted, a shielding sheet metal (102) disposed on the printed circuit board and shielding ICs with a large noise radiation amount, an unsealing rib (201) formed on the unsealing surface (203) of the shielding sheet metal (102), and a holding means (202) formed near the inside of the unsealing rib (201) on the unsealing surface (203). The unsealing surface (203) is unsealed along the unsealing rib (201) by pulling up the holding means.</p>
