An observation device includes an objective lens disposed below a container to collect light from a specimen; a surface light source that is disposed at a pupil position of the objective lens in the optical path of the illumination light, that causes illumination light to enter the container from below, and that can change a light emission pattern in a direction intersecting an emission optical axis, an imaging optical system that captures light from the specimen generated by the specimen being irradiated with the illumination light from the surface light source and focused by the objective lens below the container; and a controller that corrects a light emission pattern on a basis of the light emission pattern and at least one of a brightness, contrast, and the relationship between the number of pixels and the luminance of an acquired image with the light emission pattern.