NOVELTY - A photo-anode preparing method involves utilizing graphene nano-structure with large specific surface area as raw material, and coating inorganic nanoparticle, manganese dioxide nanometer material and graphene on surface of substrate material, followed by dissolving single layer or multilayer graphene in water or organic solvent ultrasonically to obtain graphene oxide solution. The inorganic nanoparticle and manganese dioxide nanometer material is dispersed in the graphene oxide solution ultrasonically to obtain mixed material. The mixed material is coated on surface of the substrate material.    USE - Method for preparing photo-anode used in dye-sensitized solar cell.    ADVANTAGE - The method enables preparing photo-anode with light-weight, better performance, better photoelectric conversion efficiency, better electrical conductivity, better thermal conductivity and better mechanical property in a simple and inexpensive manner.    DETAILED DESCRIPTION - A photo-anode preparing method involves utilizing (in mass%) graphene nano-structure with large specific surface area as raw material, and coating inorganic nanoparticle (40-83), manganese dioxide nanometer material (15-20) and graphene (2-40) on surface of substrate material, followed by dissolving single layer or multilayer graphene in water or organic solvent ultrasonically to obtain graphene oxide solution (10.5-28 mg/ml). The inorganic nanoparticle and manganese dioxide nanometer material is dispersed in the graphene oxide solution ultrasonically to obtain mixed material. The mixed material is coated on surface of the substrate material at normal temperature for more than 48 hours to obtain a coated material. The coated material is dried to obtain single layer or multi-layer graphene composite film, followed by carrying out reduction process on the single layer or multi-layer graphene composite film on the surface of the substrate material by using reducing agent to obtain single layer or multi-layer graphene photo-anode. The obtained photo-anode is treated under protection of nitrogen or argon gas at 650-800 degrees C to obtain a finished product.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a photo-anode.'(Drawing includes non-English language text)'