A backlight module (200) includes a fame (55) having a plurality of side walls (551, 552, 553, 554); a light guide plate (53) received in the frame, having a light incident surface (533); at least one spring element (5523), having a spring finger (5525) and a connecting arm (5524) connecting the spring finger and one side wall of the frame; and at least one radiation element (56) disposed between the spring finger and the light incident surface. The width of the at least one radiation element is larger than a distance between the light incident surface and the spring finger in a free state.