PURPOSE: To correct oil pressure in an oil pressure operating mechanism and to compensate the stable operation of the operating mechanism by controlling the impressed voltage amount of an electrostriction member corresponding to a command signal from a controller based on a detected value from an oil pressure sensor on the upstream side of the pressure control valve.

CONSTITUTION: This pressure control valve is arranged in a duct L for linking an oil pressure operating mechanism A to be operated by oil pressure supplied from an oil pressure source P and a tank T for the flow-in of oil flowing out of the operating mechanism A, and the oil pressure of the oil pressure operating mechanism A is controlled corresponding to the impressed voltage amount to an electrostriction member W. The pressure control valve is composed of a main valve 22 composed of a circular leaf valve housed in a casing member 21, back pressure chamber R formed on the back side of the main valve 22, upstream side and downstream side valves 23 and 24 composed of circular leaf valves arranged on the upstream side and backstream side of the back pressure chamber R, and electrostriction member W to change the initial load of the upstream side valve 23. Then, the impressed voltage amount to the electrostriction member W is controlled based on the detected value of a pressure sensor S.