A pneumatic tire comprising: a tread portion ; a pair of axially spaced bead portions each with a bead core embedded therein; a pair of sidewall portions extending between tread edges and the bead portions ; and a carcass extending between the bead portions through the tread portion and the sidewall portions and comprising a carcass ply , wherein the carcass ply is composed of carcass cords rubberized with a topping rubber and extending between the bead portions through the tread portion and the sidewall portions and turned up around the bead core in each of the bead portions from the axially inside to the axially outside of the tire so as to form a pair of carcass-ply turned-up portions and a carcass-ply main portion therebetween, the bead portions are each provided with a primary bead apex rubber disposed between the carcass-ply main portion and the carcass-ply turned-up portion and extending radially outwardly from the bead core , an insulation rubber layer having a radially inner edge located between the primary bead apex rubber and the carcass-ply main portion and extending radially outwardly from said radially inner edge through between the carcass-ply main portion and the carcass-ply turned-up portion , and a subsidiary bead apex rubber layer disposed axially outside the carcass-ply turned-up portion , wherein the subsidiary bead apex rubber layer has a radially outer edge , and the insulation rubber layer has a radially outer edge which is located radially outside the radially outer edge of the subsidiary bead apex rubber layer , characterized in that a complex elastic modulus (E ∗ a) of the insulation rubber layer is not smaller than a complex elastic modulus (E ∗ b) of the topping rubber of the carcass ply , and the radially outer edge of the subsidiary bead apex rubber layer is positioned in a range between a height of 30% and a height of 55% of a cross-sectional height (H) of the tire , each height measured radially outwardly from a bead base line (BL). a tread portion ; a pair of axially spaced bead portions each with a bead core embedded therein; a pair of sidewall portions extending between tread edges and the bead portions ; and a carcass extending between the bead portions through the tread portion and the sidewall portions and comprising a carcass ply , wherein the carcass ply is composed of carcass cords rubberized with a topping rubber and extending between the bead portions through the tread portion and the sidewall portions and turned up around the bead core in each of the bead portions from the axially inside to the axially outside of the tire so as to form a pair of carcass-ply turned-up portions and a carcass-ply main portion therebetween, the bead portions are each provided with a primary bead apex rubber disposed between the carcass-ply main portion and the carcass-ply turned-up portion and extending radially outwardly from the bead core , an insulation rubber layer having a radially inner edge located between the primary bead apex rubber and the carcass-ply main portion and extending radially outwardly from said radially inner edge through between the carcass-ply main portion and the carcass-ply turned-up portion , and a subsidiary bead apex rubber layer disposed axially outside the carcass-ply turned-up portion , the subsidiary bead apex rubber layer has a radially outer edge , and the insulation rubber layer has a radially outer edge which is located radially outside the radially outer edge of the subsidiary bead apex rubber layer , characterized in that a complex elastic modulus (E ∗ a) of the insulation rubber layer is not smaller than a complex elastic modulus (E ∗ b) of the topping rubber of the carcass ply , and the radially outer edge of the subsidiary bead apex rubber layer is positioned in a range between a height of 30% and a height of 55% of a cross-sectional height (H) of the tire , each height measured radially outwardly from a bead base line (BL). <EOS>