A head-mounted-display (HMD) includes a face plate, and a main body. The main body attaches the face plate to cover a front portion of the main body. The main body includes a front plate, a back plate, and a circuit board. The front plate includes at least one first air channel formed at a rear side of the front plate facing away from the face plate for conveying air from a bottom portion of the main body to an upper portion of the main body. Each of the front plates may be formed with windows for receiving an intake air or discharging an outflow air. The back plate is attached to the front plate and located further away from the face plate. The circuit board is located between the front plate and the back plate.