There is provided a new X-ray imaging apparatus by the use of which X-ray CT and panoramic imaging can be effectively performed. In an X-ray imaging apparatus which rotates an X-ray generating section and an X-ray detecting section around an imaging object arranged between these X-ray generating section and the X-ray detecting section and also detects in the X-ray detecting section X-rays having been radiated from the X-ray generating section and transmitted through the imaging object to form an X-ray image, a panoramic imaging mode in which the X-ray generating section and the X-ray detecting section are driven to form a panoramic image of the imaging object and an offset scan/CT mode in which the X-ray generating section and the X-ray detecting section are driven to form a tomographic image of the imaging object are set, so as to selectively execute these two imaging modes. Consequently, the panoramic imaging mode and the offset scan/CT mode can be arbitrarily selected, thereby allowing formation of an X-ray imaged image that is optimum for treatment.