PURPOSE: A locking apparatus for a parking brake is provided to prevent the discharge of a battery by using a solenoid valve. CONSTITUTION: A piston member(200) is connected to a spring(100). A cylinder(300) is formed on the circumference of the piston member. The cylinder comprises an oil supply hole(310) on one side. The fluid pressure is selectively supplied to the inside of the cylinder. A locking device(400) is mobile inside the piston member. The locking device controls the movement of the piston member. A solenoid valve(600) controls the movement of the locking device.
