To provide a tire for heavy load capable of effectively enhancing tire strength (breaking energy) and accomplishing light weight.

In the tire for heavy load provided with a carcass 6 and a belt layer 7, the maximum load ability is 2,500 kg or higher. The belt layer 7 is constituted such that first, second and third belt plies 7A, 7B and 7C comprising a steel cord inclined at an angle of 16-22° relative to a tire equator C are successively superposed from the inner side in a tire radial direction. Respective widths W1, W2 and W3 have a relationship of W1>W2>W3. Further, in the respective first, second and third belt plies 7A, 7B and 7C, ply strengths S1, S2 and S3 (kN/5 cm) represented by product of cutting load (kN/number) of a belt code with ends (number/5 cm) satisfy a predetermined relationship. An impact relaxing rubber layer 9 having thickness of 1.0-2.0 mm and width of 50% or higher of the width W1 of the first belt ply is arranged between the first belt ply 7A and the carcass 6. Complex modulus of elasticity E*a is 7.0-11.0 (MPa) and loss tangent is 0.10-0.20.

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