A pneumatic tire, comprising: a plurality of shoulder blocks provided side by side in a tire circumferential direction on an outermost side in a tire width direction, defined by a main groove extending in the tire circumferential direction in a tread surface of a tread portion and a plurality of subsidiary grooves intersecting the main groove; and a plurality of sipes extending along the tire width direction in the tread surface of each of the plurality of shoulder blocks and provided side by side in the tire circumferential direction, each of the plurality of sipes comprising at least an end portion terminated on an outer side in the tire width direction, a cap tread rubber forming the tread surface having JIS hardness Ha in a range of not less than 45 and not greater than 55, a snow traction index in a 0°direction being not less than 180, and a shortest distance (α) between a ground contact edge in the tire width direction of each of the plurality of shoulder blocks and an end portion on the outermost side in the tire width direction of one of the plurality of sipes being formed in a range of not less than 1.5 mm and not greater than 2.5 mm; wherein the JIS hardness is the durometer hardness measured in accordance with JIS K-6253 using a type A durometer and under a temperature of 20°C, wherein the snow traction index in a 0°direction is defined by the following mathematical Formula STI = − 6.8 + 2202 × ρ g + 672 × ρ s + 7.6 × Dg, when the pneumatic tire is mounted on a regular rim and inflated to a regular internal pressure in an unloaded state, wherein ρg is a groove density (mm/mm2) and is calculated as a ratio between the total length (mm) of all of the plurality of grooves, except the plurality of sipes, projected in the tire width direction on the ground contact surface between the ground contact edges and the total area of the ground contact region defined as the product of the tire ground contact width and tire circumferential length, wherein ρs is a sipe density (mm/mm2) and is calculated as a ratio between the total length (mm) of all of the plurality of sipes projected in the tire width direction and the total area of the ground contact region, wherein Dg is an average groove depth (mm) of all of the plurality of grooves and wherein the 0° direction means snow traction index with respect to the tire circumferential direction. a plurality of shoulder blocks provided side by side in a tire circumferential direction on an outermost side in a tire width direction, defined by a main groove extending in the tire circumferential direction in a tread surface of a tread portion and a plurality of subsidiary grooves intersecting the main groove; and a plurality of sipes extending along the tire width direction in the tread surface of each of the plurality of shoulder blocks and provided side by side in the tire circumferential direction, each of the plurality of sipes comprising at least an end portion terminated on an outer side in the tire width direction, a cap tread rubber forming the tread surface having JIS hardness Ha in a range of not less than 45 and not greater than 55, a snow traction index in a 0°direction being not less than 180, and a shortest distance (α) between a ground contact edge in the tire width direction of each of the plurality of shoulder blocks and an end portion on the outermost side in the tire width direction of one of the plurality of sipes being formed in a range of not less than 1.5 mm and not greater than 2.5 mm; wherein the JIS hardness is the durometer hardness measured in accordance with JIS K-6253 using a type A durometer and under a temperature of 20°C, wherein the snow traction index in a 0°direction is defined by the following mathematical Formula STI = − 6.8 + 2202 × ρ g + 672 × ρ s + 7.6 × Dg, when the pneumatic tire is mounted on a regular rim and inflated to a regular internal pressure in an unloaded state, wherein ρg is a groove density (mm/mm2) and is calculated as a ratio between the total length (mm) of all of the plurality of grooves, except the plurality of sipes, projected in the tire width direction on the ground contact surface between the ground contact edges and the total area of the ground contact region defined as the product of the tire ground contact width and tire circumferential length, wherein ρs is a sipe density (mm/mm2) and is calculated as a ratio between the total length (mm) of all of the plurality of sipes projected in the tire width direction and the total area of the ground contact region, wherein Dg is an average groove depth (mm) of all of the plurality of grooves and wherein the 0° direction means snow traction index with respect to the tire circumferential direction.