The present invention discloses an imaging apparatus radial-operating a transmitting and receiving unit and generating cross-sectional images inside the body cavity by a plurality of images, which includes: an X-ray image memory holding a plurality of X-ray images obtained by X-ray imaging the transmitting and receiving unit inside the body cavity by a predetermined imaging cycle, an image processing unit generating a cross-sectional moving image by setting the rotation cycle of the transmitting and receiving unit to be frame rate, and an image processing unit reading out an X-ray image, obtained from X-ray imaging just previously at every timing for every rotation cycle of the transmitting and receiving unit, from the X-ray image memory and generating an X-ray moving image by the frame rate.