At a front end of the lateral arm 6 of a surgical microscope apparatus, the apparatus has an intake port 15. A band 20 is tied around the front end of the lateral arm so that a drape P is drawn only to a surgical microscope 14. Drawing the drape to the surgical microscope results in clearing the field of vision of a surgeon D. Part of the drape around the lateral arm and a longitudinal arm 3 is not drawn, to cause no hindrance in operability of the surgical microscope. The lateral arm and the like are hollow to form an inner ventilating path without separately preparing ventilating tubes or the like for ventilation.
