An X-ray diagnosis apparatus and method for creating image data, wherein a plurality of sets of reference image data is created based on projection data obtained from a plurality of imaging directions to the object after an contrast agent is injected to an object, fluoroscopic image data are created based on projection data obtained from a desired imaging direction to the object, and fluoroscopic roadmap image data are created based on the fluoroscopic image data and reference image data whose imaging direction corresponds to the imaging direction of the fluoroscopic image data.