The invention relates to a graphene-loaded lamellar cupric oxide composite material and a hydro-thermal synthesis method thereof. The composite material is characterized in that a CuO (cupric oxide) laminar and a graphene laminar are compounded, and adopts a quasi-two dimensional nano-structure. Graphene serving as a matrix skeleton has excellent conductibility, and the CuO laminar can achieve excellent conductibility through the graphene laminar, so that the apparent electric conductivity of the composite material is improved. The lamellar cupric oxide growing on two sides of the graphene is about 200 nm in width and 300 to 500 nm in length; and a composite graphene nanosheet is 1 to 100 microns in plan view size and 1 to 20 nm in thickness. The composite material is prepared through the following two typical steps: preparing pyrolysis graphene; and obtaining the graphene-loaded lamellar cupric oxide composite material through hydro-thermal synthesis. A single electrode made of the graphene-loaded lamellar cupric oxide composite material prepared by the method is high in capacitance and good in cycling performance. Therefore, the graphene-loaded lamellar cupric oxide composite material is suitable for electrode materials of super capacitors.