Provided is a pneumatic radial tire: that includes a circumferential-direction reinforcement layer having a width increased with fatigue break of the circumferential-direction reinforcement layer being suppressed at edge portions thereof; and that suppresses separation in each of cross belt layers at edge portions thereof. A pneumatic radial tire according to the present invention is a pneumatic tire including: at least two cross belt layers disposed on an outer circumferential side of a carcass layer in a tread portion; and at least one circumferential-direction reinforcement layer disposed between these cross belt layers, a width of the circumferential-direction reinforcement layer being smaller than that of each cross belt layer. The pneumatic radial tire is configured so that: the cross belt layers are separated away from each other at outer sides respectively of end positions, in a width direction, of the circumferential-direction reinforcement layer; the circumferential-direction reinforcement layer includes steel cords of two types which differ in elongation at break; and the steel cord having relatively small elongation at break is disposed in a center portion of the circumferential-direction reinforcement layer, whereas the steel cord having relatively large elongation at break is disposed in each of outer side portions of the circumferential-direction reinforcement layer.