An airless tire comprising: a cylindrical tread ring that has a ground contact surface; a hub part that is arranged on a radial direction inner side of the tread ring and is fixable to an axle; and a spoke that connects the tread ring and the hub part, wherein the tread ring has therein a reinforcing body, the reinforcing body includes: an annular first reinforcing cord layer that extends in a tire circumferential direction; an annular second reinforcing cord layer that is arranged on a tire radial direction inner side of the first reinforcing cord layer and extends in the tire circumferential direction; and a shear layer that is formed of an elastomer and is arranged between the first reinforcing cord layer and the second reinforcing cord layer, the shear layer includes a first portion and a second portion, the second portion being formed of a material different from the first portion, the first portion is arranged in a tire axial direction central region of the shear layer, the second portion is arranged on both tire axial direction sides of the first portion, characterized in that a loss tangent (tanδ) and a shear modulus (Ee) (unit: MPa) of the first portion at a temperature of 30 °C satisfy the following Equations and, the loss tangent (tanδ) being measured according to JIS K6394 using a viscoelasticity spectrometer under conditions including an initial strain of 10%, a dynamic strain of ±1%, a frequency of 10 Hz, and a tensile deformation mode, and the shear modulus (Ee) being measured according to JIS K6251 at an elongation of 2.00%. tan ⁢ δ ≦ 0.06 Ee / tan ⁢ δ ≧ 1500 MPa a cylindrical tread ring that has a ground contact surface; a hub part that is arranged on a radial direction inner side of the tread ring and is fixable to an axle; and a spoke that connects the tread ring and the hub part, wherein the tread ring has therein a reinforcing body, the reinforcing body includes: an annular first reinforcing cord layer that extends in a tire circumferential direction; an annular second reinforcing cord layer that is arranged on a tire radial direction inner side of the first reinforcing cord layer and extends in the tire circumferential direction; and a shear layer that is formed of an elastomer and is arranged between the first reinforcing cord layer and the second reinforcing cord layer, an annular first reinforcing cord layer that extends in a tire circumferential direction; an annular second reinforcing cord layer that is arranged on a tire radial direction inner side of the first reinforcing cord layer and extends in the tire circumferential direction; and a shear layer that is formed of an elastomer and is arranged between the first reinforcing cord layer and the second reinforcing cord layer, the shear layer includes a first portion and a second portion, the second portion being formed of a material different from the first portion, the first portion is arranged in a tire axial direction central region of the shear layer, the second portion is arranged on both tire axial direction sides of the first portion, characterized in that a loss tangent (tanδ) and a shear modulus (Ee) (unit: MPa) of the first portion at a temperature of 30 °C satisfy the following Equations and, the loss tangent (tanδ) being measured according to JIS K6394 using a viscoelasticity spectrometer under conditions including an initial strain of 10%, a dynamic strain of ±1%, a frequency of 10 Hz, and a tensile deformation mode, and the shear modulus (Ee) being measured according to JIS K6251 at an elongation of 2.00%. tan ⁢ δ ≦ 0.06 Ee / tan ⁢ δ ≧ 1500 MPa