To provide a door mirror heater for a vehicle such as a motor vehicle or the like on which a high voltage battery is mounted, a door mirror heater compliant to a high voltage battery having a heat generating circuit provided with a PTC layer corresponding to a heating element and electrodes for applying a current to the PTC layer is structured such that an initial resistance value of the heat generating circuit is set between 20 and 200 .OMEGA., more preferably between 50 and 100 .OMEGA., a lower limit value of a PTC characteristic R.sub.100.degree. C./R.sub.25.degree. C. is set to 10, more preferably, to 50, and a rubber is added to a main material polymer of the PTC layer, and a metal oxide is added as a filler.