Provided is a medical observation device which includes a detection unit configured to detect a pressing operation based on an operation signal according to the pressing operation which is output from an external operation device equipped with a switch pressed by a mouth, and a processing unit configured to perform a process corresponding to the detected pressing operation. The process corresponding to the pressing operation includes some or all of a process related to an imaging operation of an imaging device, a process related to a display of a medical captured image which is captured in the imaging device, and an identification process of identifying a user's input indicating the process related to the imaging operation or the process related to the display of the medical captured image.
