A heavy duty tire including bead portions each with a bead core, and a carcass ply containing a main portion extending between bead portions and a pair of edge portions wound around the bead cores, the wound edge portion including a turnback part extending axially inwardly from a position on the axially outside of the bead core and an auxiliary cord layer disposed on the radially outside of the turnback part, whereby the end of the turnback part is positioned at a distance of from 2.0 to 8.0 mm from the radially outer surface of the bead core. In a normally inflated unloaded state of the tire, the turnback part is curved such that the diameter of the turnback part decreases continuously from the end to the position in the axial outside of the bead core.