A medical observation apparatus includes: an imaging device configured to capture an observation target to obtain a captured right eye medical image and a captured left eye medical image； and circuitry configured to: acquire positions of at least two points in the observation target, the positions being determined based on predetermined operation on the observation target； and cause the captured right eye medical image, the captured left eye medical image, and an annotation image, to be displayed on a display screen of a display device, the annotation image indicating a distance between two points at the acquired positions.
