To improve early abrasion of a center part while showing stone bite prevention effect in a pneumatic radial tire for heavy load.

This radial tire has three peripheral direction grooves 2 extending to tire peripheral direction T on a tread surface 1 and one of the peripheral direction grooves 2 is arranged in a center part and other two are arranged at both sides of the center part and a land part 3 divided by the three peripheral direction grooves 2 is formed and a stone bite preventing projected part 5 is disposed in a groove bottom 2a of the peripheral direction groove 2A arranged in the center part. In this case, a projected shaped part 6 is disposed along the tire peripheral direction T in the groove bottom 2b of the two peripheral direction groove 2B at both sides and also height of the projected shaped part 6 and that of the stone bite preventing projected part 5 are changed so that the height of the stone bite preventing projected part 5 is lower.