The present invention provides a backboard, a backlight module, and a liquid crystal display device. The backboard is configured by at least two units interconnected together, wherein the backboard includes a bottom and sidewall extending from edge of the bottom, wherein the sidewall is provided with at least a fastener which is implemented by attaching a screw onto the sidewall. The backboard is configured by two interconnected units so as to reduce the manufacturing cost. The backlight module and the liquid crystal display device are also benefited with reduced manufacturing cost. The backboard is provided with fastener implemented by attaching a screw. Accordingly, this arrangement is specially suitable for the situation in which the fasteners can not be integrally formed with the backboard. This arrangement is further beneficial for the assembling of the backlight module.