A surge tank with an air intake control valve for an internal-combustion engine, the air intake control valve comprising: a valve body rotatably mounted on the surge tank, rotated between an open position and a closed position to open and close a fluid passage formed in a partition wall internally dividing the surge tank into two parts; and a valve body sealing member arranged on an outer periphery of the valve body, providing a seal between the partition wall and the valve body by coming into contact with the partition wall of the surge tank at the closed position of the valve body, wherein the valve body is configured to rotate about a rotation shaft line, characterized in that a rotation shaft rotating together with the valve body is integrally provided on a first end portion of the valve body, in an extensional direction of the rotation shaft line (Ll), a first shaft bearing is integrally provided on a second end portion of the valve body in the extensional direction of the rotation shaft line (Ll), the rotation shaft of the valve body is rotatably supported by a second shaft bearing fixed to a rotation shaft support portion provided on an outer peripheral wall of the surge tank while the first shaft bearing of the valve body is rotatably supported by a shaft member fixed to a shaft member fixing portion of the partition wall of the surge tank, the second shaft bearing is inserted into and mounted in a clearance between an outer peripheral surface of the rotation shaft and an inner peripheral surface of a rotation shaft support hole in a state where the rotation shaft is inserted into the rotation shaft support hole of the rotation shaft support portion, so that the rotation shaft is rotatably supported by the second shaft bearing, and the rotation shaft support hole is so configured that the inner diameters of a small diameter portion, a medium diameter portion, and a large diameter portion are increased in a stepwise manner from the inside of the surge tank toward the outside thereof. a valve body rotatably mounted on the surge tank, rotated between an open position and a closed position to open and close a fluid passage formed in a partition wall internally dividing the surge tank into two parts; and a valve body sealing member arranged on an outer periphery of the valve body, providing a seal between the partition wall and the valve body by coming into contact with the partition wall of the surge tank at the closed position of the valve body, wherein the valve body is configured to rotate about a rotation shaft line, characterized in that a rotation shaft rotating together with the valve body is integrally provided on a first end portion of the valve body, in an extensional direction of the rotation shaft line (Ll), a first shaft bearing is integrally provided on a second end portion of the valve body in the extensional direction of the rotation shaft line (Ll), the rotation shaft of the valve body is rotatably supported by a second shaft bearing fixed to a rotation shaft support portion provided on an outer peripheral wall of the surge tank while the first shaft bearing of the valve body is rotatably supported by a shaft member fixed to a shaft member fixing portion of the partition wall of the surge tank, the second shaft bearing is inserted into and mounted in a clearance between an outer peripheral surface of the rotation shaft and an inner peripheral surface of a rotation shaft support hole in a state where the rotation shaft is inserted into the rotation shaft support hole of the rotation shaft support portion, so that the rotation shaft is rotatably supported by the second shaft bearing, and the rotation shaft support hole is so configured that the inner diameters of a small diameter portion, a medium diameter portion, and a large diameter portion are increased in a stepwise manner from the inside of the surge tank toward the outside thereof.