A backlight module comprises a back frame, a light guide plate disposed in the back frame, and elastic corner parts for locating the light guide plate. The elastic corner parts are disposed at diagonal corners of the backlight module and sandwiched between the back frame and the light guide plate. The elastic corner parts can locate the light guide plate in the back frame, and the desirable cushioning performance and appropriate hardness of the elastic corner parts provide a desirable space for thermal expansion and contraction of the light guide plate. Meanwhile, the elastic corner part corresponding to the light incident side is greater than that of the non-light-incident sides for ensuring the light mixing distance between the LEDs and the light incident side of the light guide plate, which can improve the light unitization factor of the LEDs and save both the product cost and the mold cost.