The present invention relates to a 3-dimensional nanostructure having nanomaterials stacked on a graphene substrate; and more specifically, to a 3-dimensional nanostructure having at least one nanomaterial selected from nanotubes, nanowires, nanorods, nanoneedles and nanoparticles grown on a reduced graphene substrate. The present invention enables the achievement of a synergy effect of the 3-dimensional nanostructure hybridizing 1-dimensional nanomaterials and 2-dimensional graphene. The nanostructure according to the present invention is excellent in flexibility and elasticity, and can easily be transferred to any substrate having a non-planar surface. Also, all junctions in nanomaterials, a metal catalyst and a graphene film system form the ohmic electrical contact, which allows the nanostructure to easily be incorporated into a field-emitting device.