PURPOSE: To prevent leaver wear effectively and prevent lowering of braking and driving performances on a wet road.

CONSTITUTION: A radial tire for heavy load is provided with a plurality of linear longitudinal grooves 3 continuing in the tire circumferential direction and ribs of which end parts are adjacent to the above vertical grooves 3, on the treading face and formed with a linear upper groove wall 6 which inclines at such an angle as narrowing the groove width of a longitudinal groove 3 from the treading face opening end 7 of the longitudinal groove 3 toward the groove bottom 8 and a zigzag lower groove wall 9 which has the inclination angle larger than the upper groove wall 6 and periodically repeats projections 10 and recessions 11 in zigzags in the tire circumferential direction.