Provided are a device and method capable of machining a machining target such as a sample, a probe, or a sample table without requiring a high degree of device operation skill. First, a shape generation process of determining a shape of a machining target on the basis of an ion beam scanning signal and an absorption current of the machining target is performed. Next, a machining pattern positioning process of positioning a machining pattern over an image of the machining target is performed. Further, an ion beam stopping process of stopping ion beam irradiation is performed from a result of comparison between the image of the machining target and the machining pattern while the machining target is machined through the ion beam irradiation.