To closely adhere a resistance-welded surface, and to remarkably improve bonding strength by performing arc welding after connecting mounting tube on the tip part of a main body with resistance welding.

In the main body 1 of a hollow stabilizer, a thick wall 2 is formed by upsetting at its tip part. While pushing strongly the main body 1 of the hollow stabilizer on the outer peripheral surface of the tube 3 from the right-angled direction, a high voltage is applied. Then, Joule heat is generated by a current flowing through the joined surfaces, the tip part of the main body 1 is softened and crushed, and is welded on the tube 3, including apart 2a projected to inner and outer peripheries. Next, by performing the arc welding to the outer periphery of the joined part of the main body 1 and the tube 3, a bead 4 is formed. Therefore, the joined surfaces are made to closely adhere by resistance welding, and an inner peripheral surface is welded as well, and since the double welding of resistance welding and arc welding is performed, bonding strength is remarkably improved.