A backlight module and a display module are provided. The backlight module includes a back plate, a light guide plate, and a light source. The back plate includes a receiving cavity. One side of the back plate is formed with a through hole. The light guide plate is disposed in the receiving cavity. A light incident surface of the light guide plate corresponds to the through hole, the light source is disposed in the through hole, and the light source corresponds to the light incident surface of the light guide plate. By forming the through hole on one side of the back plate and providing the light source in the through hole, a side frame is not required to be provided, a thickness of a frame of the backlight module is reduced, and a narrow frame is realized.