A door handle device capable of operating a door opening/closing mechanism of a vehicle is disclosed. The door handle device includes a support member, a door handle, a circuit substrate, a lock detection electrode, a capacitance sensor, and an auxiliary electrode. The circuit substrate is arranged in the door handle and includes a ground electrode. The lock detection electrode is mounted on the circuit substrate and capacitance-coupled to an outer panel of the door. The capacitance sensor is connected to the lock detection electrode and detects the issuance of a door lock command based on a change in a first capacitance between the outer panel and the lock detection electrode. The auxiliary electrode is capacitance-coupled to the ground electrode to form a second capacitance connected in parallel to the first capacitance between the auxiliary electrode and the ground electrode.