A variable displacement compressor in which variable control of
displacement is effected through adjustment of a crank chamber pressure,
includes: a suction port; a suction chamber; a suction passage
establishing communication between the suction port and the suction
chamber; and an opening control valve arranged in the suction passage and
adapted to adjust the opening of the suction passage based on a pressure
difference between a suction pressure in the suction port and the crank
chamber pressure.