A resistance welding method for welding conductive cylindrical first and second members to each other in a coaxial manner by bringing end portions (42a, 43a) of the first and second members into contact with each other, characterized in that the conductive cylindrical first member includes a flange portion at an end at which the conductive cylindrical first member is welded to the conductive cylindrical second member the resistance welding method comprising the steps of: (a) preparing a first electrode having an insertion hole and a columnar guide pin that is insertable into the insertion hole; (b) positioning the guide pin and the first member by inserting the guide pin and the first member into the insertion hole such that the insertion hole, the first member, and the guide pin are coaxial with each other, that the first electrode contacts the flange portion that the guide pin extends through the cylindrical first member, and that the flange portion of the first member to be welded and a portion of the guide pin project from the insertion hole, wherein the outer peripheral surface of the first member is separated from the inner surface of the insertion hole by a distance M, and M is greater than zero; (c) positioning the second member by inserting the guide pin into the cylindrical second member such that the flange portion of the first and the end portion of the second member contact each other, that the first and second members are coaxial with each other, and that the second member does not contact the first electrode; and (d) welding the first and second members to each other at contact surfaces thereof by positioning a second electrode such that the second electrode contacts the second member but does not contact the first electrode and applying a voltage between the first and second electrodes to conduct a current through the contact surfaces of the first and second members while the first and second members are pressed in directions toward each other, wherein the guide pin is made of ceramic and a clearance is provided between the guide pin and an inner surface of the insertion hole in the state in which the guide pin is inserted in the insertion hole, the clearance allowing the guide pin to tilt in a radial direction of the guide pin while the state in which the first and second members contact each other is maintained when the current is conducted in (d). (a) preparing a first electrode having an insertion hole and a columnar guide pin that is insertable into the insertion hole; (b) positioning the guide pin and the first member by inserting the guide pin and the first member into the insertion hole such that the insertion hole, the first member, and the guide pin are coaxial with each other, that the first electrode contacts the flange portion that the guide pin extends through the cylindrical first member, and that the flange portion of the first member to be welded and a portion of the guide pin project from the insertion hole, wherein the outer peripheral surface of the first member is separated from the inner surface of the insertion hole by a distance M, and M is greater than zero; (c) positioning the second member by inserting the guide pin into the cylindrical second member such that the flange portion of the first and the end portion of the second member contact each other, that the first and second members are coaxial with each other, and that the second member does not contact the first electrode; and (d) welding the first and second members to each other at contact surfaces thereof by positioning a second electrode such that the second electrode contacts the second member but does not contact the first electrode and applying a voltage between the first and second electrodes to conduct a current through the contact surfaces of the first and second members while the first and second members are pressed in directions toward each other,