An observation-point arranging unit arranges an observation point indicating a portion to be included in a slice area on a positioning image displayed on a display device. A scanning-condition receiving unit receives a specification of a scanning condition including number of movements of a couch on which an object is placed during scanning and a size of the slice area. A slice-area setting unit sets the slice area including the observation point for each position to which the couch is to be moved, based on the observation point and the scanning condition. A scanning unit scans the object multiple times while moving the couch, based on the slice area.