The invention discloses a combined implementation method for airborne video compression and target tracking, which utilizes current video compression algorithm to extract intermediate data from the video compression algorithm, meanwhile acquires a relative motion vector by compensating the obtained data with a global motion vector acquired by calculating the various parameters of airplanes and rotational stations. Afterwards the relative motion vector is analyzed and calculated; a pixel block with relatively large relative motion vector weight is found; the position and the shape of the pixelblock are determined, then the image region where a moving target is located is detected, and real time tracking of the moving target in the obtained ground image can be realized by an unmanned aerial vehicle. The tracking method of the invention has the advantages that, image compression and moving target tracking can be realized at the same time; the real time property and the reliability are good; wrong detection and miss detection do not occur when multiple targets are detected at the same time; meanwhile hardware resources are saved and the method can be easily realized.