A variable-capacity compressor control valve (1, 2) comprising: a valve body including a chamber (21,20Cb) with a valve orifice, a Ps inlet/outlet port communicating with a suction chamber of a compressor, a Pd introduction port arranged upstream of the valve orifice and communicating with a discharge chamber of the compressor, and a Pc inlet/outlet port arranged downstream of the valve orifice and communicating with a crank chamber of the compressor; a valve element adapted to open or close the valve orifice; an electromagnetic actuator with a plunger for moving the valve element in a direction to open or close the valve orifice; a pressure-sensitive chamber adapted to receive a suction pressure Ps from the compressor via the Ps inlet/outlet port; and a pressure-sensitive reaction member adapted to urge the valve element in the direction to open or close the valve orifice in accordance with a pressure in the pressure-sensitive chamber, wherein the valve element is adapted to be slidably fitted and inserted into a guide hole provided in the valve body, and one of the valve element or the valve body is provided with a flexible or elastic sealing member, the sealing member being adapted to, when the valve orifice is closed by the valve element, abut an end portion on a higher pressure side in a gap between sliding surfaces that is formed between the valve element and the guide hole, and thus seal the gap between the sliding surfaces, characterized in that the sealing member is arranged in the chamber (21,20Cb) and disposed in an annular groove (15h,15i), the annular groove (15h,15i) being provided around an outer periphery of the valve element, wherein a) a lower surface of the annular groove and a bottom surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the lower surface and the bottom surface of the chamber such that the gap is sealed, or wherein b) an upper surface of the annular groove and an upper surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the upper surface and the upper surface of the chamber such that the gap is sealed. a valve body including a chamber (21,20Cb) with a valve orifice, a Ps inlet/outlet port communicating with a suction chamber of a compressor, a Pd introduction port arranged upstream of the valve orifice and communicating with a discharge chamber of the compressor, and a Pc inlet/outlet port arranged downstream of the valve orifice and communicating with a crank chamber of the compressor; a valve element adapted to open or close the valve orifice; an electromagnetic actuator with a plunger for moving the valve element in a direction to open or close the valve orifice; a pressure-sensitive chamber adapted to receive a suction pressure Ps from the compressor via the Ps inlet/outlet port; and a pressure-sensitive reaction member adapted to urge the valve element in the direction to open or close the valve orifice in accordance with a pressure in the pressure-sensitive chamber, wherein the valve element is adapted to be slidably fitted and inserted into a guide hole provided in the valve body, and one of the valve element or the valve body is provided with a flexible or elastic sealing member, the sealing member being adapted to, when the valve orifice is closed by the valve element, abut an end portion on a higher pressure side in a gap between sliding surfaces that is formed between the valve element and the guide hole, and thus seal the gap between the sliding surfaces, characterized in that the sealing member is arranged in the chamber (21,20Cb) and disposed in an annular groove (15h,15i), the annular groove (15h,15i) being provided around an outer periphery of the valve element, wherein a) a lower surface of the annular groove and a bottom surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the lower surface and the bottom surface of the chamber such that the gap is sealed, or wherein b) an upper surface of the annular groove and an upper surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the upper surface and the upper surface of the chamber such that the gap is sealed. a) a lower surface of the annular groove and a bottom surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the lower surface and the bottom surface of the chamber such that the gap is sealed, or wherein b) an upper surface of the annular groove and an upper surface of the chamber are adapted to be substantially flush with each other when the valve orifice is closed by the valve element, the sealing member being adapted to be pressed by the pressure in the chamber so as to be tightly in contact with the upper surface and the upper surface of the chamber such that the gap is sealed.