The invention discloses a preparation method of a graphene paper-metal composite material. According to the preparation method, graphene paper is tightly attached to a cathode, the cathode and an anode are immersed in an electrolyte, the anode is connected with a positive electrode of a power source, and the cathode is connected with a negative electrode of the power source. Metal is adopted forthe anode, metal ions are generated by electrolysis of the anode when the power source is powered on, metal ions are generated on the graphene paper of the cathode, and a metal coating is generated onthe graphene paper of the cathode, so that compounding of the graphene paper and the metal is achieved, the preparation process is simple, the time consumption is short, the energy consumption is low, the thickness of a plating layer is easy to control, and industrialization can be realized.