A backlight module is suitable for use in a liquid crystal display. The backlight module includes a back plate, and a lamp, over the back plate by a distance. The back plate has a hole under the lamp. The hole can be a hole under the lamp corresponding to an electrode of a high voltage end of the lamp. The hole or a certain number of the holes can be replaced by an indentation, which can also effectively increase the separation distance between the lamp and the back plate. Actually, the hole and the indentation can be used together to form a desired pattern corresponding to the lamp. The lamp can be a plurality of lamp.