A head-mounted display apparatus (1) includes an image display part (10) configured to display an image, an optical unit (20, 30, 50) configured to lead the image to an eye of a wearer of the display apparatus (1), a light intensity detector (60) configured to detect light intensity (A) of external light, a dimmer filter (40) configured to vary transmittance to adjust the intensity (B) of the external light reaching the eye of the wearer, and a controller (70) configured to adjust the transmittance of the dimmer filter (40) and the light intensity (C) of a light source of the image display part (10) based on the light intensity (A) of the external light obtained by the light intensity detector (60).