A solenoid valve comprising: a cylindrical sleeve with a plurality of ports (41, 42, 44) formed therein through which a working fluid flows; a shaft-like spool that moves through the sleeve in an axial direction to open and close the ports (41, 42, 44); and a solenoid portion that moves the spool in the axial direction with respect to the sleeve, wherein the solenoid portion includes a tubular solenoid coil supplied with a current to generate a magnetic force; a cover member made of a magnetic material surrounding the solenoid coil; a shaft supported so as to be movable in the axial direction along a central axis of the solenoid coil to apply an axial moving force to the spool; a plunger that is movable in the axial direction along with the shaft, and a magnetic material core that attracts the plunger using the magnetic force generated in the solenoid coil, wherein the cover member has an outer tubular portion that covers an outer periphery of the solenoid coil, a first bottom portion that covers an end of the solenoid coil that is on the opposite side to the sleeve, an inner tubular portion interposed between the plunger and an end of the solenoid coil close to the first bottom portion, and a second bottom portion formed to protrude inward in a radial direction with respect to the inner tubular portion and facing the plunger in the axial direction, the magnetic material core is interposed between the shaft and the solenoid coil in the radial direction and faces the plunger and the inner tubular portion of the cover member in the axial direction, and the magnetic material core has a cylindrical portion with an insertion hole which is formed in a central portion of the cylindrical portion and through which the shaft is inserted, and a flange portion that couples the cylindrical portion and the outer tubular portion of the cover member together, the shaft is supported by a first bearing portion formed on the magnetic material core so as to contact an outer peripheral surface of the shaft in a sliding manner, wherein the first bearing portion is formed such that a part of the cylindrical portion of the magnetic material core in the insertion hole protrudes inward in the radial direction to form a sliding contact surface which contacts an outer peripheral surface of the shaft in a sliding manner, and a second bearing portion supporting the shaft is formed on the second bottom portion of the cover member, wherein the second bearing portion is formed by forming, in the second bottom portion of the cover member, a sliding hole in which the shaft protruding from the plunger is held so as to slide freely, wherein an inner peripheral surface of the second bearing portion is formed as a sliding contact surface that is in sliding contact with the outer peripheral surface of the shaft. a cylindrical sleeve with a plurality of ports (41, 42, 44) formed therein through which a working fluid flows; a shaft-like spool that moves through the sleeve in an axial direction to open and close the ports (41, 42, 44); and a solenoid portion that moves the spool in the axial direction with respect to the sleeve, wherein the solenoid portion includes a tubular solenoid coil supplied with a current to generate a magnetic force; a cover member made of a magnetic material surrounding the solenoid coil; a shaft supported so as to be movable in the axial direction along a central axis of the solenoid coil to apply an axial moving force to the spool; a plunger that is movable in the axial direction along with the shaft, and a magnetic material core that attracts the plunger using the magnetic force generated in the solenoid coil, wherein the cover member has an outer tubular portion that covers an outer periphery of the solenoid coil, a first bottom portion that covers an end of the solenoid coil that is on the opposite side to the sleeve, an inner tubular portion interposed between the plunger and an end of the solenoid coil close to the first bottom portion, and a second bottom portion formed to protrude inward in a radial direction with respect to the inner tubular portion and facing the plunger in the axial direction, the magnetic material core is interposed between the shaft and the solenoid coil in the radial direction and faces the plunger and the inner tubular portion of the cover member in the axial direction, and the magnetic material core has a cylindrical portion with an insertion hole which is formed in a central portion of the cylindrical portion and through which the shaft is inserted, and a flange portion that couples the cylindrical portion and the outer tubular portion of the cover member together, the shaft is supported by a first bearing portion formed on the magnetic material core so as to contact an outer peripheral surface of the shaft in a sliding manner, wherein the first bearing portion is formed such that a part of the cylindrical portion of the magnetic material core in the insertion hole protrudes inward in the radial direction to form a sliding contact surface which contacts an outer peripheral surface of the shaft in a sliding manner, and a second bearing portion supporting the shaft is formed on the second bottom portion of the cover member, wherein the second bearing portion is formed by forming, in the second bottom portion of the cover member, a sliding hole in which the shaft protruding from the plunger is held so as to slide freely, wherein an inner peripheral surface of the second bearing portion is formed as a sliding contact surface that is in sliding contact with the outer peripheral surface of the shaft.