A reflective sheet, a backlight module and a display device are disclosed. The reflective sheet (20) includes a reflective sheet body (201) provided with a plurality of opening areas and an open-closed structure (202) located in each of the opening areas. The open-closed structure (202) comprises at least a movable type vane, and one side of the movable type vane is connected with an edge of the opening area of the reflective sheet body. The movable type vane has a reflective surface, and the reflective surface of the movable type vane is disposed on the same side as a reflective surface of the reflective sheet body. The reflective sheet body is able to alleviate the interference in reflection effect of light ray due to the positioning posts, thus, a good display quality can be achieved.