The utility model discloses a bus safety door which comprises two internal movable door plates and two door armrests, wherein the joint parts of the two internal movable door plates are respectively and symmetrically provided with the door armrests which are internally provided with sensors; the fronts and the sides of the door armrests are provided with small holes; the small hole of one door armrest is internally embedded with an electrooptical signal transmitting tube, and the other door armrest is internally embedded with an electrooptical signal receiving tube; the upper and the lower ends of rotating shafts of the internal movable door plates are respectively provided with a sensor box; the surfaces of the sensor boxes are provided with small holes; and the transmitting tube and the receiving tube are embedded into the small holes on the surfaces of the sensor boxes. The bus safety door is low in cost, easy to popularize, light to take, durable in use and attractive in appearance.