A control valve comprising: a common body having: a lead-in port through which a working fluid is led into; a lead-in/out port through which the working fluid is led into or led out from; a lead-out port from which the working fluid is lead out; a first valve hole through which the lead-in port and the lead-out port communicate; and a second valve hole through which the lead-in/out port and the lead-out port communicate, the second valve hole being disposed along the same axis line as that of the first valve hole; a first valve element configured to regulate an opening degree of a first valve by moving toward and away from the first valve hole; a second valve element configured to open and close a second valve by moving toward and away from the second valve hole and configured to communicate between the lead-in/out port and the lead-out port, characterised by the second valve element having a third valve hole whose diameter is smaller than that of the second valve hole; a third valve element configured to regulate an opening of a third valve by moving toward and away from the third valve hole, the third valve element being provided in such a manner as to be integrally displaceable the first valve element, a biasing member configured to bias the second valve element in a closing direction of the second valve and in an opening direction of the third valve; a common actuator configured to electrically control the opening degrees of the first valve, the second valve and the third valve; and a valve actuating member configured to be driven by the actuator in a direction of axis line and configured to transmit a drive force, which acts in opening and closing directions of each valve, to the first valve element. a common body having: a lead-in port through which a working fluid is led into; a lead-in/out port through which the working fluid is led into or led out from; a lead-in port through which a working fluid is led into; a lead-in/out port through which the working fluid is led into or led out from; a lead-out port from which the working fluid is lead out; a first valve hole through which the lead-in port and the lead-out port communicate; and a second valve hole through which the lead-in/out port and the lead-out port communicate, the second valve hole being disposed along the same axis line as that of the first valve hole; a first valve element configured to regulate an opening degree of a first valve by moving toward and away from the first valve hole; a second valve element configured to open and close a second valve by moving toward and away from the second valve hole and configured to communicate between the lead-in/out port and the lead-out port, characterised by the second valve element having a third valve hole whose diameter is smaller than that of the second valve hole; a third valve element configured to regulate an opening of a third valve by moving toward and away from the third valve hole, the third valve element being provided in such a manner as to be integrally displaceable the first valve element, a biasing member configured to bias the second valve element in a closing direction of the second valve and in an opening direction of the third valve; a common actuator configured to electrically control the opening degrees of the first valve, the second valve and the third valve; and a valve actuating member configured to be driven by the actuator in a direction of axis line and configured to transmit a drive force, which acts in opening and closing directions of each valve, to the first valve element.