A pneumatic tire having a pair of bead portions; bead cores each having a polygonal cross section; a radial carcass having respective ends wound around the corresponding bead cores from the inner to outer side; one layer of wire chafer disposed outwardly of the radial carcass relative to the bead core; and a rubber chafer in a contact area between the bead portion and a prescribed rim, wherein, in a cross section of the tire assembled with the prescribed rim, the angle between the bottom side of the bead core and a bead seat of the prescribed rim is in the range of 0±2°, and a portion, on the tire outer surface side, of an outermost layer filament of steel cords constituting the wire chafer extends at an angle in the range of 90±5° relative to the extending direction of ply cords of the radial carcass.