The invention provides an ultra-high-definition display control method and an ultra-high-definition display control device as well as an ultra-high-definition television, wherein the ultra-high-definition display control method comprises the following steps that received 4K*2K signals are resolved into 2K*1K transition signals; the 2K*1K transition signals are subjected to decoding processing, and 2K*1K screen display signals are obtained; and the 2K*1K screen display signals are converted into 4K*2K target signals, the 4K*2K target signals are provided for an ultra-high-definition screen, and the ultra-high-definition display is realized. For a film source of 4K*2K signals, the film source is resolved into the 2K*1K transition signals so that the traditional television chip can conveniently carry out the decoding processing, the 2K*1K screen display signals are obtained, the 2K*1K screen display signals subjected to the decoding processing are synthesized into the 4K*2K target signals, and the goal that the ultra-high-definition screen realizes the ultra-high-definition display on ultra-high-definition signals is reached.