PURPOSE: To simplify the forming work of a tire and improve its strength and durability, by constituting a ply of the tire with a hollow body in which a belt- shaped material is sprirally wound.

CONSTITUTION: A ply constitutional material 1' consisting of several layers of cords and rubbers for closely attaching these cords is spirally wound to form a hollow shaped ply 1 with its section almost in a round shape. External construction 2 comprises a tread 3 and side wall 4 which constitute the outer sking of a tire and a breaker 5 interposed between the tread 3 and the ply 1. In this way, under the condition that the ply 1 is sealed with air in its inside and mounted to a rim 8, a portion of the ply 1 corresponding to the rim 8 can be surely held its figure and closely attached to the rim to surely prevent its separation from the rim 8 and eliminate the necessity for providing a bead. While the ply 1 and the external construction 2 are welded in a vulcanization process further the inner circumferential side of the tire of the ply 1 is closely attached to the rim 8 to ensure its air-tightness.