RUN-FLAT TIRE

Provided is a run flat tire comprising a side reinforcing layer on a sidewall part, wherein a rubber composition of the side reinforcing layer has a complex elastic modulus at 100°C (E*) of 5.0 to 17 MPa and a loss tangent at 60°C (60°C tan δ) of 0.020 to 0.100 MPa, and wherein, where a tire cross-sectional width is defined as Wt (mm) and a tire outer diameter is defined as Dt (mm), Wt and Dt satisfy any of the following inequality (1), (2), and (3): Wt < 225 and Dt ≥ 59.078 × Wt ∧ 0.460 225 ≤ Wt < 235 and Dt ≥ 59.078 × Wt ∧ 0.620 − 967.673 235 ≤ Wt and Dt ≥ Wt ∧ 0.6 + 750