Abstract: A head-mounted display comprises a wearing frame able to be mounted on head, a support frame, a video output terminal module and at least one display unit. Since the display unit can be combined with or detached from the video output terminal module, the head-mounted display can be changed into right-eye mode, left-eye mode, or twin-eyes mode. The video output terminal module is connected to the wearing frame through the support frame. The support frame is used to adjust the relative positions between the wearer and the display units along a vertical direction, a transverse direction, or a front-back direction.