Provided is a cross-section processing and observation apparatus, including a control portion for repeatedly executing a process including slice processing by an ion beam and acquisition of a SIM image by a secondary electron emitted from a cross-section formed by the slice processing, in which the control portion divides an observation image into a plurality of areas, and finishes the process when a change has occurred between an image in one area of the plurality of areas and an image in an area, which corresponds to the one area, of an observation image of another cross-section acquired by the process.