A method and a system for controlling a parking brake of a motor vehicle are described. According to the described method, an ignition signal and an actuation state of the parking brake are detected. An application force of the parking brake is then set to a first value in dependence upon the actuation state of the parking brake if the ignition signal is present. If the parking brake was previously in an applied actuation state, the application force is reduced from a second value to the first value. If the parking brake was previously in a released actuation state, the application force is increased to the first value. The first value is sufficient to hold the motor vehicle in its current position.