Abstract: The disclosure relates to a rear cover of backlight module, a backlight module and a display module. The rear cover includes a bottom plate and one or more side plates, wherein an accommodating cavity is formed by the side plates and the bottom plate, an inner surface of a side plate is provided with a protrusion protruding toward inside of the accommodating cavity, and a groove used to accommodate the backlight source and fix a light guide plate is formed between the protrusion and the bottom plate. The backboard, the plastic central frame and the front frame of a display module such as television are integrated into one. This dramatically reduces the components or the key materials for the display module, thereby shortening the supply chain and saving the cost for the materials. Several key materials are integrated into one, so that the cost may be lowered.