Heavy load pneumatic radial tire according to the present invention includes: tread rubber 6 having laminated structure of cap rubber 5 and base rubber 4; and four or more belt layers 3a-3e disposed radially inward of tread rubber 6. A radially outer side of a width direction side edge of at least one of radially outermost belt layer 3e and widest-width belt layer 3c is covered by reinforcing rubber layer 7 that terminates on a radially inner side of tread rubber 6 without reaching tire equatorial plane E. Relative relation between reinforcing rubber constituting reinforcing rubber layer 7 and base rubber 4 in terms of modulus of rebound elasticity satisfies the condition: reinforcing rubber