To enable observation of the operating site to be continued more easily in the case in which the picture of the operating site is no longer displayed normally.
Provided is a surgical microscope device including: a microscope unit that images an observation target, and outputs a picture signal; a support unit that supports the microscope unit, and is configured as a balance arm; and an auxiliary observation device that is attachable to the microscope unit or the support unit, and is configured to enable observation of an observation range provided by the microscope unit.