This disclosure has one object to provide radiation tomography apparatus that allows acquisition of a sectional image having an accurately mapped radiopharmaceutical localization in an internal structure of a subject. According to one embodiment, a top board stops several times between a starting position forwardly in a top board movement direction and a termination position backwardly in the top board movement direction. Both CT image and the PET image are acquired upon stop of the top board. With the conventional method, the subject in the PET image and that in the CT image deviate from each other in position. In contrast to this, with the configuration of this disclosure, assumed that once movement of the top board is one step, a CT image taken two steps before has been acquired in every taking of the PET image by several times. Superimposing of these images may realize accurate mapping of radiopharmaceutical localization in the internal structure of the subject.
