A digital X-ray photography device, including an X-ray tube unit, a rotation supporting unit for rotating around a subject, an image system unit installed on the rotation supporting unit, for detecting X-rays transmitted through the subject, a first image processing unit, installed on the rotation supporting unit, for constructing a rotational stereoscopic image of the subject based on a signal from the image system unit, an X-ray detector, installed on the rotation supporting unit, for detecting X-rays transmitted through the subject, a second image processing unit, installed on the rotation supporting unit, for constructing a CT image of the subject based on a signal from the X-ray detector, and a unit for controlling pulse-shaped X-rays to be continuously radiated during a forward rotation and a backward rotation of the rotation supporting unit in order to perform a rotational stereoscopic photographing.