The invention belongs to the field of preparation of composite electrode materials, and in particular relates to preparation of an electrode material of a piece of sandwich structured composite graphene oxide paper. The electrode material of the sandwich structured composite graphene oxide paper is prepared through a one-step method. The method specifically comprises the following steps of ultrasonically dispersing graphite oxide in a solvent, adding transition metal salt to discontinuously stir, such that the system is uniformly mixed, reacting at 80-150 DEG C for 8-12 h after adjusting pH to alkalinity, and performing suction filtration, washing and drying at low temperature so as to obtain the electrode material of the sandwich structured composite graphene oxide paper. To improve the electrochemical property of the electrode material, the electrode material is roasted and immersed in electrolyte after being roasted. The preparation material is cheap and available in raw material, simple and convenient in process operation and low in production cost, and is suitable for industrial production; and furthermore, the prepared electrode material has excellent electrochemical property.