A run-flat tire, comprising: a pair of bead portions including at least a bead core; a carcass arranged from the one bead portion to the other bead portion; and a reinforcing rubber layer arranged from a buttress portion including an outside end of a tread portion in a width direction and a sidewall portion communicating to the buttress portion and has a crescent sectional shape along a tread width direction and a tire diameter direction, the run-flat tire further comprising: a side reinforcing layer arranged along the reinforcing rubber layer; and a turned-back bead reinforcing layer arranged along the bead portion and turned back around the bead core from inside to outside in the tread width direction, wherein the turned-back bead reinforcing layer comprises: a bead reinforcing layer main portion arranged inside the bead portion in the tread width direction, and a turned-back portion communicated to the bead reinforcing layer main portion and turned back around the bead core from the inside to the outside in the tread width direction, characterized in that: the side reinforcing layer is configured by a side reinforcing layer organic fiber cord, and in that the turned-back bead reinforcing layer is configured by a turned-back bead reinforcing layer organic fiber cord having a higher tension than that of the side reinforcing layer organic fiber cord. a pair of bead portions including at least a bead core; a carcass arranged from the one bead portion to the other bead portion; and a reinforcing rubber layer arranged from a buttress portion including an outside end of a tread portion in a width direction and a sidewall portion communicating to the buttress portion and has a crescent sectional shape along a tread width direction and a tire diameter direction, the run-flat tire further comprising: a side reinforcing layer arranged along the reinforcing rubber layer; and a turned-back bead reinforcing layer arranged along the bead portion and turned back around the bead core from inside to outside in the tread width direction, wherein a side reinforcing layer arranged along the reinforcing rubber layer; and a turned-back bead reinforcing layer arranged along the bead portion and turned back around the bead core from inside to outside in the tread width direction, wherein a bead reinforcing layer main portion arranged inside the bead portion in the tread width direction, and a turned-back portion communicated to the bead reinforcing layer main portion and turned back around the bead core from the inside to the outside in the tread width direction, characterized in that: the side reinforcing layer is configured by a side reinforcing layer organic fiber cord, and in that the turned-back bead reinforcing layer is configured by a turned-back bead reinforcing layer organic fiber cord having a higher tension than that of the side reinforcing layer organic fiber cord. the side reinforcing layer is configured by a side reinforcing layer organic fiber cord, and in that the turned-back bead reinforcing layer is configured by a turned-back bead reinforcing layer organic fiber cord having a higher tension than that of the side reinforcing layer organic fiber cord.