The X-ray imaging device includes an X-ray generator to generate an X-ray and radiate the X-ray to an object, an X-ray detector to detect the X-ray passing through the object and acquire an image signal of the object, and a controller to analyze the image signal of the object, evaluate a characteristic of the object and generate at least one of a single energy X-ray image and a multiple energy X-ray image according to the evaluated characteristic. FIG. 1
