To suppress strength decrease and fatigue of ply cord at a side protrusion and recess site even in the case of aging use by adhering a reinforcing material to an inner surface side of a tire at the side protrusion and recess site.

When an external damage or rubbed damage occurs at a side of a carcass layer 6 of a radial tire 1, a protrusion and recess A (side protrusion and recess site A) is locally generated at its part. This occurs due to that a ply cord 5 is plastically deformed. Thus, a reinforcing material 11 of a patch-like state is adhered to an inner surface side of the tire of the side protrusion and recess site A with adhesive to be reinforced. As the material 11, repairing patch sold in the market is used, formed of rubber, and embedded with many rayon cords 12 at an interval therein. The cords 12 are disposed in its axial direction toward a tire radial direction, and adhered. In this case, tension of the cord 5 is loaded particularly to the cords 12 to alleviate tension loading of the cord 5, thereby suppressing progress of strength decrease and fatigue.