To facilitate manufacture and to improve quality by providing a flange part to extend in the outer peripheral direction on one end end part of an outside cylinder of a bush by charging a fixed member in a hollow part of a connecting part of an arm and providing a caulking part to fix the bush in a hole part of the connecting part of the arm on the other end end part.

A bush 1 and an arm 21 are connected to each other as the other end end part of an outside cylinder 4 of the bush 1 is caulked and fixed in a hole part 22a of the arm 21 on which the hole part 22a made of a hollow material and passing through one end part in the axial vertical direction is formed in connecting structure of the bush 1 and the arm 21. At this time, as a fixed member 23 is charged in the hollow material of a connecting part 22 of the arm 21, the connecting part 22 is never contracted even when pressure is applied on the connecting part 22 of the arm 21 at the time of caulking the other end end part of the outside cylinder 4 of the bush 1. Consequently, as welding work is eliminated, and it is possible to provide high strength, and additionally to improve quality as roundness can be secured.