An electromagnetic interference shielding film includes an insulation layer, a first adhesive layer, a porous metal layer and a conductive adhesive layer including a plurality of conductive particles. The first adhesive layer is located between the insulation layer and the porous metal layer, and the porous metal layer is formed on the first adhesive layer, and making the first adhesive layer locate between the porous metal layer and the insulation layer. The conductive adhesive layer is located on the porous metal layer so that the porous metal layer is located between the first adhesive layer and the conductive adhesive layer. The present invention further provides a preparation method thereof.