In an X-ray computer tomographic apparatus according to an embodiment, an image processing unit generates a projection image and a sectional image based on projection data generated from output of an X-ray detector. When at least one end of a scan range of second scan is set on part of a projection image generated based on projection data acquired through first scan by the image processing unit, a scan plan processing unit displays a sectional image corresponding to at least one end of the scan range among sectional images generated based on projection data acquired through the first scan by the image processing unit.
