The present invention is a device that creates a template based on design data without performing an exposure simulation, etc., and an object thereof is to provide a pattern matching image forming device capable of forming an image that is commensurate with the size of the actual pattern. As one mode for achieving the object above, there is proposed a pattern matching image forming device that, in forming a matching image, shrinks or enlarges design data based on a desired pattern size, and that forms a matching image based on a pattern thus shrunk or enlarged.