A thin 3D reduced graphene oxide(rGO)/CNT/Fe3O4 composite based on carbon film with outstanding electromagnetic wave interference shielding capability was fabricated by solvothermal method and electrophoresis. Then,multi-layered composites were prepared based on epoxy resin. The influence of electric field and deposition time on the morphology of the graphene oxide nanosheet and conductivity and shielding efficiency of 3D rGO/CNT/Fe3O4/epoxy composites was analyzed. 3D rGO/CNT/Fe3O4/epoxy composite with 4-layer has a thickness of 1.4mm, and its shielding effectiveness is up to 49.7dB in the X-band frequency range. More significantly, its specific shielding effectiveness is as high as 35.5dB/mm, which surpasses the value of most of the current carbon-based composites, and its tensile strength is 52MPa. Therefore, the successful fabrication of this novel material signifies the potential of the use of graphene as a thin and highperformance EMI shielding material.