An antenna unit incorporated into a door handle of a vehicle includes: an unlock sensor plate (first detection electrode) of a capacitive sensor configured to detect a driver's approaching or touching the door handle; and an antenna for wireless communications. The unlock sensor plate has an antenna fixing part for positioning and fixing the antenna. The antenna fixed on the antenna fixing part and the unlock sensor plate are molded into a unit with a molded resin. The unlock sensor plate has a circuit board fixing part for positioning and fixing a circuit board including a detection circuit of the capacitive sensor mounted thereon. An electrode fixing part for positioning and fixing a lock sensor plate (a second detection electrode) of the capacitive sensor is provided on an opposite surface of the circuit board from a surface on which the unlock sensor plate is arranged.