This cross-section observation device bombards an object with a charged particle beam to repeatedly expose cross-sections of the object, bombards at least some of the cross-sections from among the plurality of the exposed cross-sections with a charged particle beam to acquire cross-sectional image information describing each of the at least some of the cross-sections, generates for each of these cross-sections a cross-sectional image described by the cross-sectional image information acquired, and generates a three-dimensional image in which the generated cross-sectional images are stacked together. This cross-section observation device displays a first three-dimensional image along with a second three-dimensional image, the first three-dimensional image being a three-dimensional image from the stacking of first cross-sectional images, which are cross-sectional images of the cross-sections described by the corresponding cross-sectional image information acquired on the basis of a first condition, and the second three-dimensional image being a three-dimensional image from the stacking of second cross-sectional images, which are cross-sectional images of the cross-sections described by the corresponding cross-sectional image information acquired on the basis of a second condition.