A mirror image shielding structure is provided, which includes an electronic element and a ground shielding plane below the electronic element. The shape of the ground shielding plane is identical to the projection shape of the electronic element, and the horizontal size of the ground shielding plane is greater than or equal to that of the electronic element. Thus, the parasitic effect between the electronic element and the ground shielding plane is effectively reduced, and the vertical coupling effect between electronic elements is also reduced. Furthermore, the vertical impact on the signal integrity of the embedded elements caused by the layout of the transmission lines is prevented.