A pneumatic tire includes a carcass ply with carcass cords. The carcass cords comprise high tenacity vinylon fiber, polyethylene naphthalate fiber or polyalylate fiber. Viscoelasticity characteristics per one cord at 120° C. of the carcass cord satisfy the following equations (1) to (3): B>0  (1) B≦0.0000437×A+0.042857  (2) B≦−0.00003636×A+0.163636  (3) (wherein “A” represents a product of complex modulus E*(N/cm2) and cross-sectional area “S” (cm2) of cord), and “B” represents a loss tangent tanδ).