A heavy duty tire with decreased rolling resistance without impairing durability, comprising carcass 6, belt layer 7 disposed radially outward of the carcass in tread portion 2, and sidewall rubber 3g disposed axially outward of the carcass in sidewall portion 3 and extending in the radial direction of the tire, wherein the sidewall rubber includes an axially inner rubber portion 10 disposed axially outward of the carcass and an axially outer rubber portion 11 disposed axially outward of the inner rubber portion to form the tire outer surface, the inner rubber portion 10 has a lower loss tangent "tan .delta." than the outer rubber portion 11 by a difference of 0.010 to 0.035, and the inner rubber portion 10 has a lower complex elastic modulus than the outer rubber portion 11 by a difference of 0.5 to 1.4 MPa.