To provide a pneumatic tire which improves low rolling resistance and significantly improves run-flat durability.

(a) A rubber composition for a side-reinforcing layer 5 and/or a bead filler 7 contains (A) a rubber component and (B) 55 pts.mass of carbon black with respect to 100 pts.mass of the rubber component, wherein the rubber composition has such physical properties as vulcanized rubber that the elastic modulus at 100% elongation elasticity (M100) is 10 MPa or more and the Σ value of a tangent loss tanδ at 28 to 150°C is 6.0 or less. Furthermore, a carcass ply is constituted of reinforcing cords covered by coating rubber. As this coating rubber, (b) a carcass coating rubber composition, whose loss tangent (tanδ) on 1% strain at 25°C is 0.12 or less, is used.

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