A control valve for a variable displacement compressor for varying a discharging capacity of the compressor for compressing refrigerant led into a suction chamber and discharging the compressed refrigerant from a discharge chamber, by regulating a flow rate of the refrigerant led into a crankcase from the discharge chamber, the control valve comprising: a body having a discharge chamber communication port communicating with the discharge chamber, a crankcase communication port communicating with the crankcase, and a valve hole formed in a passage connecting the discharge chamber communication port and the crankcase communication port; a valve element for opening and closing a valve section, the valve element being arranged in such a manner as to move toward and away from the valve hole; a solenoid, provided in the body, which generates a solenoidal force with which to drive the valve element in a closing direction in accordance with an amount of current supplied; and a transmitting rod (34, 68) that transmits the solenoidal force to the valve element, the transmitting rod (34, 68) being slidably supported in a direction of axis line in the body, the solenoid including: a bottomed sleeve secured to the body wherein a pressure of refrigerant is introduced to an interior of the sleeve; a core secured coaxially to the sleeve; a plunger, contained in the bottomed sleeve on a bottom side thereof and disposed opposite to the core in the direction of axis line, the plunger being displaceable integrally with the transmitting rod (34, 68) in the direction of axis line; a first spring that applies a biasing force in a valve opening direction to the transmitting rod (34, 68); a second spring that applies a biasing force in a valve closing direction to the plunger; characterised in that the solenoid further including a supporting member, which is press-fitted such that the supporting member is secured to an inner wall of the bottomed sleeve near a bottom portion thereof, wherein the second spring is set between the supporting member and the plunger, and a pressure is applied to the supporting member by deforming the bottom portion of the bottomed sleeve in the direction of axis line so as to regulate a press-fitting position of the supporting member relative to the bottomed sleeve, whereby a set load of the first spring and the second spring is adjusted. a body having a discharge chamber communication port communicating with the discharge chamber, a crankcase communication port communicating with the crankcase, and a valve hole formed in a passage connecting the discharge chamber communication port and the crankcase communication port; a valve element for opening and closing a valve section, the valve element being arranged in such a manner as to move toward and away from the valve hole; a solenoid, provided in the body, which generates a solenoidal force with which to drive the valve element in a closing direction in accordance with an amount of current supplied; and a transmitting rod (34, 68) that transmits the solenoidal force to the valve element, the transmitting rod (34, 68) being slidably supported in a direction of axis line in the body, the solenoid including: a bottomed sleeve secured to the body wherein a pressure of refrigerant is introduced to an interior of the sleeve; a core secured coaxially to the sleeve; a plunger, contained in the bottomed sleeve on a bottom side thereof and disposed opposite to the core in the direction of axis line, the plunger being displaceable integrally with the transmitting rod (34, 68) in the direction of axis line; a first spring that applies a biasing force in a valve opening direction to the transmitting rod (34, 68); a second spring that applies a biasing force in a valve closing direction to the plunger; characterised in that the solenoid further including a supporting member, which is press-fitted such that the supporting member is secured to an inner wall of the bottomed sleeve near a bottom portion thereof, wherein the second spring is set between the supporting member and the plunger, and a pressure is applied to the supporting member by deforming the bottom portion of the bottomed sleeve in the direction of axis line so as to regulate a press-fitting position of the supporting member relative to the bottomed sleeve, whereby a set load of the first spring and the second spring is adjusted. a bottomed sleeve secured to the body wherein a pressure of refrigerant is introduced to an interior of the sleeve; a core secured coaxially to the sleeve; a plunger, contained in the bottomed sleeve on a bottom side thereof and disposed opposite to the core in the direction of axis line, the plunger being displaceable integrally with the transmitting rod (34, 68) in the direction of axis line; a first spring that applies a biasing force in a valve opening direction to the transmitting rod (34, 68); a second spring that applies a biasing force in a valve closing direction to the plunger; characterised in that the solenoid further including a supporting member, which is press-fitted such that the supporting member is secured to an inner wall of the bottomed sleeve near a bottom portion thereof, wherein the second spring is set between the supporting member and the plunger, and a pressure is applied to the supporting member by deforming the bottom portion of the bottomed sleeve in the direction of axis line so as to regulate a press-fitting position of the supporting member relative to the bottomed sleeve, whereby a set load of the first spring and the second spring is adjusted.