The present dental handpiece has a burr sleeve, a head section, an air supply passage for introducing compressed air into the head section for driving the burr sleeve, and an air discharge passage for discharging the compressed air. The air supply passage includes a through hole axially extending through the rear terminal part of the handpiece, and a tubular pressure regulating member and an air supply tube connected in series between the through hole and the head section. The pressure regulating member has an aperture for allowing communication with the air discharge passage, and an annular valve body arranged axially slidably for opening/closing the aperture. When the pressure of compressed air passing through the air supply passage exceeds a predetermined level, the valve body is slid to open the aperture to discharge the compressed air for regulating the pressure of the compressed air to be supplied to the burr sleeve.