The invention discloses a diffusion plate support which is used for a directly downward type LED backlight module. The diffusion plate support comprises a base and a cone arranged on the base, the cone is made of a semi-transparent material, the surface of the cone is a frosted surface, the base is made of a white lighttight material, and a triangular pyramid mini-structure is arranged on the surface of the base. Meanwhile, the cone and the base are integrally formed. When the diffusion plate support is utilized, light emitted by an LED can partially penetrate through the semi-transparent cone of the support. In addition, due to the fact that the surface of the semi-transparent cone is of an atomization particle structure and has a diffusion function, so that shadow cannot be generated on the surface of a screen, and the problem of cross shadow produced by a traditional diffusion plate support can be solved. In addition, due to the fact that the surface of the base part is of a white triangular pyramid microstructure, high reflectivity is achieved, the problem that the surface of the screen of a liquid crystal panel also becomes a shadow area is solved, and a display effect is more uniform.