Run-flat radial tyre

Provided is a run-flat radial tire that has a tire cross-sectional height of 115 mm or more and includes: a carcass extending between a pair of bead parts; a side-reinforcing rubber layer disposed on a tire side part and extending in a tire radial direction along the inner surface of the carcass; and one or more slanting belt layers located outside the carcass in the tire radial direction and having cords extending in a direction slanting with respect to a tire circumferential direction, wherein the width of overlap between the maximum width slanting belt layer, which has the largest width of the one or more slanting belt layers in a tire axis direction, and the side-reinforcing rubber layer in the tire axis direction is equal to or greater than 22.5 % of the tire cross-sectional height at one or both ends of the maximum width slanting belt layer in the tire axis direction.