The utility model discloses a ventilating fan orifice door, which comprises a door plate, an outer door frame, an inner door frame and an axial flow fan, wherein the door plate is hinged with the front face of the outer door frame; an inner frame edge of the outer door frame is riveted with a circle of metal edge covering strip; a rectangular dust-proof screen plate is sealed at the drift diameter of the junction of the outer door frame and the inner door frame and is connected with the axial flow fan in the inner door frame through a bolt and a nut; the side face frame edge of the outer door frame is fixedly provided with an automatic window opening mechanism; the automatic window opening mechanism can penetrate through a through hole at a corresponding position on the edge of the dust-proof screen plate to be connected to a poking rod on the frame edge of the inner door frame; the poking rod is connected with a louver which is fixedly arranged at an air outlet of the inner door frame; and a touch head is arranged at the edge of the door plate. In the mode, the axial flow fan is built in the ventilating fan orifice door, and the louver is opened and closed by using the automatic window opening mechanism. When the door plate is opened, the touch device loses pressure, a spring mechanism shrinks, and the poking rod is pulled by a connecting rod to move downwards so as to open the louver; and contrarily, the louver is closed.