To provide a base tire for improving low fuel consumption, and improving external damage resistance of a shoulder near a road surface of a sidewall.

This base tire P includes the sidewall, a bead, a carcass ply 8 and a belt, and is vulcanized in advance before sticking a tread member Q, and has a side rubber member (A)3 extending to a distance of 0.09-0.30 along a sidewall surface from a tread member interface surface end Xa, when assuming a distance to a bead bottom surface end along the sidewall surface from the tread member interface surface end Xa as 1, and the side rubber member (A)3 includes a rubber component of 100 pts.mass selected by one kind or more from natural rubber, synthetic isoprene rubber, polybutadiene rubber and styrene-butadiene copolymer rubber, and carbon black of 40-100 pts.mass of the nitrogen adsorption specific surface area (measured in response to N₂SA, JISK6217-2:2001) of 70-150 m²/g.