A head-mounted display (HMD) device includes: an HMD unit comprising a display panel configured to display an image and at least one lens for viewing the image on the display panel at a close distance; a distance-sensing sensor provided on the HMD unit to sense a distance between a user and the HMD unit to make the HMD unit be spaced apart from the user by a preset distance and avoid contact with the user; and a unit movement mechanism configured to position the HMD unit in front of the eyes of the user based on information sensed by the distance-sensing sensor to make the HMD unit avoid contact with the user.