The present disclosure relates to a graphene-nanomaterial complex, a flexible and stretchable complex including the same, and methods for manufacturing the complexes. A graphene-nanomaterial complex according to a first aspect of the present disclosure includes a plurality of graphenes and nanomaterials disposed between the graphenes, in which the graphenes are not disposed on the same plane to form a three-dimensional (3D) graphene structure, and the graphenes, the nanomaterials or both form an electrical network.