To provide a parking brake device capable of performing car height adjustment even when the parking brake is operated while the number of component parts is held less and a rise of costs is suppressed as much as practicable.

When a car height adjustment is executed in the condition that a braking force is given to all wheels by parking brake means 4 and 5, a second opening/closing valve 14 is switched from the open to closed position or vice versa, and thereby the working fluid supply condition to the parking brake means 4 and 5 for either the front wheels or the rear wheels via bypass pipe lines 1b2 and 1b3 is changed over, which disengages the parking brake means 4 and 5 for either the front wheels or the rear wheels irrespective of the operating condition of a first opening/closing valve 2.