An X-ray CT apparatus comprises an X-ray radiation source configured to radiate X-rays toward an object, an X-ray detector including a plurality of X-ray detection segments, each of which includes a plurality of detection elements, a rotation control unit configured to control rotation of the X-ray radiation source, a reconstruction unit configured to reconstruct a tomographic image based on data collected by the X-ray detector. As one aspect of the X-rays CT apparatus, there is provided a fluoroscopic image creation unit configured to create a fluoroscopic image on a plane that crosses X-ray path connecting focus of the X-ray source to the center of the X-ray detector. As another aspect of the X-rays CT apparatus, there is provided an X-ray detector which is shaped arc. As another aspect of the X-rays CT apparatus, there is provided an operation unit configured to operate a position of the X-ray radiation source. As another aspect of the X-rays CT apparatus, there is provided a data conversion unit configured to convert cone beam data into parallel beam data and a fluoroscopic image creation unit configured to create a fluoroscopic image on a plane based on the parallel beam data.