PROBLEM TO BE SOLVED: To provide an easy-to-use wire joining method capable of joining a wire and an adjustment member, while preventing the deterioration of corrosion resistance due to residual flux and eliminating the need for providing redundant parts space.SOLUTION: The wire joining method comprises: a wire insertion step of inserting a wire 12 at least into the inside of a caulking portion 11b of an adjustment member 11 and a caulking step of joining the adjustment member 11 and the wire 12 in the caulking portion 11b by plastically deforming the caulking portion 11b with a pressing force applied to the outer peripheral surface of the caulking portion 11b. The adjustment member 11 comprises: a male screw portion 11a which is provided in an area on one end side in a height direction and has a cylindrical shape with both ends opened to allow the wire 12 to be inserted therethrough, and which has a screw thread formed on the outer peripheral surface and the caulking portion 11b which is provided in an area on the other end side in the height direction, namely an area different from the area on the one side in the height direction, and which plastically deforms with a pressing force applied to the outer peripheral surface thereof to allow joining to the wire 12.
