PURPOSE: To provide a parking brake device capable of sufficiently lightening an operating force of an operating lever even without needing separately an energy source like a pum, being simplified and reducing cost.

CONSTITUTION: A parking brake device is provided with an operating lever 1 for operating a parking brake B1, a pressure generating means 6 for generating brake pressure for a main brake, an actuator 5 for operatively receiving the brake pressure to drive the parking brake B1 in the operating direction and a switch 38 for detecting that the operating lever 1 is operated in the direction of operating the parking brake. A solenoid valve 32 is provided which is interposed in an inflow path 21 between the pressure generating means and actuator 5, while closing normally the inflow path 21 and opening the inflow path when the switch 38 detects the operating lever 1 operated in the operating direction.