The invention discloses a preparation method of a quantum dot sensitized solar cell photo-anode of a multilayer structure. The preparation method is specifically implemented according to the followingsteps: 1, preparing TiO2 nanocrystalline slurry; 2, preparing a TiO2 nanocrystalline membrane of a multi-layer porous structure; 3, preparing the quantum dot sensitized photo-anode. According to thephoto-anode prepared by the method disclosed by the invention, the light capture intensity is improved, the absorption range of a spectrum is expanded, and the light absorption is enhanced, so that the battery efficiency is improved.