NOVELTY - Preparation of a porous spherical titanium dioxide comprises preparing a titanium dioxide precursor by adding cetylamine to absolute ethyl alcohol, adding potassium chloride solution while stirring, adding isopropyl titanate, stirring, and drying; and adding the titanium dioxide precursor in mixture of absolute ethyl alcohol, deionized water, and ammonia water, heating the solution to 160 degrees C, reacting for 16 hours at a constant temperature, removing ammonia in the reaction solution by rotationally evaporating at 50 degrees C, and washing with alcohol.    USE - Method for the preparation of a porous spherical titanium dioxide used in preparing a light positive electrode of a dye sensitized solar battery (claimed).    ADVANTAGE - The method is simple, has low energy consumption, and allows repeatability. The porous spherical titanium dioxide has high specific surface area and high photochemical stability, and has more than 50% efficiency for absorbing dye and transmitting electron.    DETAILED DESCRIPTION - Preparation of a porous spherical titanium dioxide comprises:    (A) preparing a titanium dioxide precursor by adding cetylamine to absolute ethyl alcohol, carrying out ultrasonic mixing, adding potassium chloride solution while stirring to obtain mixture I, rapidly adding isopropyl titanate to the mixture I, stirring the solution to obtain a white suspension, standing and separating the suspension to obtain solid in the suspension, and drying the solid in the suspension, where the molar ratio of isopropyl titanate, cetylamine, water, potassium chloride, and alcohol is 1:(0.3-1):(3-4):0.0055:(200-250); and    (B) adding the titanium dioxide precursor in mixture of absolute ethyl alcohol, deionized water, and ammonia water, transferring the solution in a closed reactor, heating the solution to 160 degrees C, reacting for 16 hours at a constant temperature, where the volume ratio of the absolute ethyl alcohol to the deionized water is 2:1, the molar concentration of the ammonia water in the mixture of the ethyl alcohol and the deionized water is 0.2-0.5 mol/L, the mass ratio of the titanium dioxide precursor to the deionized water is 1: (6-1):7, transferring the reaction solution out of the closed reactor after cooling the closed reactor to the room temperature, removing ammonia in the reaction solution by rotationally evaporating at 50 degrees C, and washing with alcohol.    An INDEPENDENT CLAIM is included for preparing a light positive electrode of a dye sensitized solar battery, comprising coating a slurry of the porous spherical titanium dioxide on transparent conductive glass, sintering the glass for 30 minutes at 500 degrees C, forming a porous spherical titanium dioxide film layer, cooling the film layer at 80 degrees C, soaking the film layer in N719 dye, standing the film layer for 24 hours, extracting and washing the film layer with alcohol, and drying the film layer with nitrogen.