A control valve in a compressor that adjusts the discharge displacement based on controlling of an inclination of a cam plate. The compressor includes a supply passage for connecting a discharge chamber with a crank chamber. The control valve is placed midway on the supply passage. The control valve has a valve body. The valve body moves in a first direction to open the supply passage and moves in the second direction to close the supply passage. A reacting member reacts to suction pressure. A first transmitting member is placed between the reacting member and the valve body. A solenoid is opposed to the reacting member with respect to the valve body. The solenoid urges the valve body in the second direction via a second transmitting member when the solenoid is excited. An urging device urges the valve body in the first direction, The first transmitting member connects the reacting member with the valve body to move the valve body toward or away from the reacting member. The urging device causes the valve body to fully open the supply passage when the solenoid is de-exited.