NOVELTY - A photo-anode of dye-sensitized solar cell is prepared by dissolving block polymer (0.5-5 g) to absolute alcohol (25-50 ml), adding hydrochloric acid (0.1-1 ml) and acetylacetone (0.2-2 ml), mixing for 0.5-6 hours, adding precursor solution of titanium (1-15 ml), adding deionized water (0-15 ml), performing film-forming by spin-coating for 20-60 seconds at 1000-3000 rpm, annealing conductive substrate in air or oxygen at 350-450 degrees C for 5-30 minutes, and annealing mesoporous titanium-dioxide film at 400-500 degrees C for 2 hours.    USE - Method for preparing a photo-anode of dye-sensitized solar cell (claimed).    ADVANTAGE - The mesoporous titanium-dioxide electrode has a high specific surface area, high porosity, and uniform aperture distribution. The flash annealing saves the time. Due to the repeated spin-coating and flash annealing technology, it is easy to control the thickness of mesoporous titanium-dioxide electrode.    DETAILED DESCRIPTION - Preparation of photo-anode of dye-sensitized solar cell involves dissolving block polymer (0.5-5 g) to absolute alcohol (25-50 ml), upon thorough dissolution, adding hydrochloric acid (0.1-1 ml) with 1 mol/L concentration and acetylacetone (0.2-2 ml), and mixing for 0.5-6 hours. Precursor solution of titanium (1-15 ml) is added. After 30 minutes, deionized water (0-15 ml) is added and mixed at normal temperature to obtain a precursor sol of titanium. Film-forming is performed by spin-coating for 20-60 seconds at 1000-3000 rpm to make the prepared precursor sol of titanium be a film on a conductive substrate. The conductive substrate is annealed in air or oxygen at 350-450 degrees C for 5-30 minutes, and naturally cooled to room temperature. The spin-coating and annealing steps are repeated to obtain mesoporous titanium-dioxide film with a thickness of 100 nm to 20 mu m. The mesoporous titanium-dioxide film is annealed at 400-500 degrees C for 2 hours, and naturally cooled to room temperature to obtain mesoporous titanium-dioxide photo-anode.