A production method of a backlight plate, a backlight plate and a backlight module are provided. The method includes providing a light-transmitting substrate which comprises a first area and a second area, forming a pad on the light-transmitting underlay substrate corresponding to the first area, coating a layer of photosensitive material on the light-transmitting substrate and the pad to form a reflective layer, exposing a position of the second area at opposite sides of the light-transmitting substrate that the reflective layer corresponds to, and developing the reflective layer to form a groove for exposing the pad on the first area that the reflective layer corresponds to. The present disclosure ensures the stability of the reflective layer and enhances the overall reflectance of the backlight plate.