A pneumatic radial tire to be fitted on a wheel in which a position wherein a disc is joined to a rim is offset from the center of the width of the rim toward the outer surface of said wheel, characterized in that the tire comprises an asymmetric structure in which a belt layer is provided between a tread and a carcass layer, an outer circumferential portion of the belt layer being covered with at least one belt covering layer, the at least one belt covering layer being disposed so that an average position of the center(s) of the width(s) thereof from the equator of the tire is deviated toward the opposite side of the offset side of the disc, a ratio e/w of the deviating distance e to the width w of a ground contacting portion of the tread being set to 0.05-0.13.