A diffuser plate with higher light diffusion efficiency and brightness applied to backlight module of Liquid Crystal Display TV (LCD TV) for providing uniform light is disclosed. An optical lens with a diffusion layer is disposed on one side of the substrate. The diffusion layer is arranged above the optical lens for enhancing diffusion effect. The other side of the diffuser plate can be a plane or having a lens structure. By Lenticular lens, the homogeneity of emitted light is improved so as to reduce the amount of diffusion particles being added into the diffusion plate Therefore, the light transmission is increased and the brightness is enhanced. Meanwhile, ability of shielding lamps is considered and Moire effect is eliminated. Moreover, the diffusion layer is co-extruded on surface of the Lenticular lens together with the substrate so that the device is easy to be produced.