Abstract: A hairdryer includes a casing, a flow duct provided within the casing and having an intake port and a delivery port, a motor unit including an electric motor, and at least one rotor, which can be driven in rotation by the electric motor and is configured for sucking in an air flow through the intake port and sending it into the flow duct towards the delivery port. At least one electrical resistance is inserted in the flow duct and configured for heating the air flow taken in by the aforesaid rotor. The at least one electrical resistance is coated with electrically insulating material, and the motor unit includes a watertight casing housing the electric motor.