The embodiment of the invention discloses a method for controlling an aircraft to descend. The method comprises the following steps: when the aircraft is at a flight state, acquiring a target real-time image, wherein the target real-time image is photographed through a vertically downward aircraft camera when the aircraft is at the flight state; according to the target real-time image, acquiring a position for descending; determining a deviation value between the aircraft and the position for descending; and according to the deviation value, sending a descending control instruction to the aircraft, so as to descend the aircraft to the position for descending according to the descending control instruction. The invention further provides a device for controlling the aircraft to descend. According to the method and the device, provided by the embodiment of the invention, the aircraft can automatically descend to a target position; in a descending process, the image is acquired through the camera and the target position is positioned through utilizing the acquired image; and the aircraft is not easily influenced by external factors so that the descending accuracy of the aircraft is improved.