A shielding structure of a circuit board and an electronic device having the structure are disclosed. The electronic device includes a casing, a circuit board and a shielding structure. The shielding structure includes a shielding film and a ground guide member electrically configured on the circuit board. The shielding film includes two insulation layers and a metal layer placed between the two insulation layers, hence forming a sandwich structure. One of the insulation layers is adhered to the circuit board and is provided with an opening. The metal layer is exposed via the opening to form a guide portion, such that the shielding film can be electrically connected to the ground guide member through the exposed guide portion to further be grounded. Thus, complete noise shielding effects and efficient noise grounding effects are achieved.