A variable displacement compressor comprises a housing forming a crank chamber, a shaft, expansible chambers including pistons, a swash plate connected to the shaft so as to be smoothly changeable in inclination against the shaft and driven to rotate, a wobble plate rotatable on the swash plate, a rotation preventing mechanism including a shoe member slidable in an axial direction, and a pressure control valve which is provided in a refrigerant passage from a suction port of the compressor to the expansible chamber to control the pressure of refrigerant to be sucked responsive to the suction pressure and both to the suction pressure and to the discharge pressure when the discharge pressure is high. The refrigerant passage has a sharply bent portion for separating lubrication oil from a refrigerant flowing therein and communicates with the crank chamber to discharge blow-by gas therefrom.