An embodiment of an tomographic image generating system may include: an imaging member that includes a radiation source, a radiation detector and a subject table, and captures the projected image a predetermined number of times while changing a positional relationship between the radiation source and the radiation detector a reconstructing member that generates a tomographic image of the subject from the projected image captured by the imaging member an acquiring member that acquires a thickness of the subject and/or a two-dimensional shape of a surface of the subject, the surface of the subject being irradiated with radiation and a controlling member that determines an imaging condition for the imaging member and/or a reconstructing condition for the reconstructing member generating the tomographic image of the subject, on the basis of the thickness and/or the two-dimensional shape of the subject acquired by the acquiring member.
