Disclosed are a backlight module and a display device. The backlight module comprises: a back plate, comprising a bottom plate (10), side plates (12), and bent parts (13), and the bottom plate, the side plates, and the bent parts form an mounting space (14) in an enclosing manner; a reflective sheet (20) arranged on the bottom plate; a light guide plate (30) arranged on a side, facing away from the bottom plate (11), side of the reflective sheet (20); a film (40) arranged on a side, facing away from the reflective sheet (20), of the light guide plate (30).