The invention discloses a preparation method of a graphene base electrode for an asymmetric capacitance deionization device and belongs to the technical field of capacitance deionization. The asymmetric capacitance deionization device comprises two electrodes which start from single precursors (GO), one of the electrodes takes graphene coated with magnesium-doped aluminium oxide as the positive electrode material, the other electrode takes reduced type oxidized graphene as the negative electrode material, the positive electrode material used by the positive electrode has positive charge, and the negative electrode material used by the negative electrode has negative charge. According to the preparation method of the graphene base electrode for the asymmetric capacitance deionization device, the same ion exclusion effect in the adsorption process can be reduced, electrical loss caused by the same ion exclusion effect is reduced, certain backward voltage can be applied favorably in the adsorption process so as to obtain more ionic adsorption points, and further the desalination performance of the capacitance deionization device is improved.