The present invention relates to a method and device for estimating a distance to a target, and a unmanned aerial vehicle. The method is applicable to a unmanned aerial vehicle including a photographing device. The method includes: acquiring a current frame of image of the target captured by the photographing device; acquiring location information of the target according to the current frame of image, where the location information includes a height of the target and two-dimensional pixel coordinates of the target in the image; acquiring attitude information of the photographing device, where the attitude information includes a pitch angle of the photographing device; and acquiring a distance between the target and the unmanned aerial vehicle according to the location information of the target and the attitude information of the photographing device.