Light guide plate used for LED backlight module and machining method of light guide plate

The invention discloses a light guide plate used for an LED backlight module and a machining method of the light guide plate. The light guide plate (1) converts light rays emitted by an LED lamp (2) and comprises a light entering face (11), a light outlet face (12) used for leading the light rays out of the light guide plate (1), and a reflection face (13) opposite to the light outlet face (12), wherein the light outlet face (12) and the reflection face (13) are not parallel to each other. A pattern structure is arranged on the reflection face (13) and is composed of a plurality of diffusion lattice points (14) which can reflect incident light rays in a diffused mode and emit the light rays out of the light outlet face (12). Compared with a direct injection molding method, the light guide plate which is of the structure and used for the LED backlight module and the machining method of the light guide plate have the advantages that the lattice points have designability, cost can be saved, the luminance uniformity of the light outlet face can be conveniently changed, and the display effect can be improved.