The invention discloses an unmanned aerial vehicle control method, device and system, wherein the unmanned aerial vehicle is provided with a camera device and a holder for installing the camera device. The method comprises the following steps: acquiring an image acquired by the camera device, and responding to touch operation aiming at a target shooting object in the image to acquire a target rotation angle of the holder; judging whether the target rotation angle of the holder is larger than a first preset angle, and acquiring the expected flying height of the unmanned aerial vehicle accordingto the judgment result that the target rotation angle of the holder is larger than the first preset angle; and converting the expected flying height of the unmanned aerial vehicle into an unmanned aerial vehicle flying control mode instruction, and sending the unmanned aerial vehicle flying control mode instruction to the unmanned aerial vehicle to be adjusted to the expected flying height.