A sample observation device (1) includes: an emission optical system (3) for emitting planar light (L2) onto a sample (S); a scanning unit (4) for scanning the sample (S) with respect to an emission face (R) of the planar light (L2); an imaging optical system (5) having an observation axis (P2) inclined with respect to the emission face (R) and for forming an image from observation light (L3) generated in the sample (S) in accordance with the emission of the planar light (L2); an image acquiring unit (6) for acquiring a plurality of partial image data corresponding to a part of an optical image according to the observation light (L3) formed as an image by the imaging optical system (5); and an image generating unit (8) for generating observation image data of the sample S based on the plurality of partial image data generated by the image acquiring unit (6).