A run-flat tire, comprising a rim, a tire skin, and one or more elastomers, wherein the elastomer(s) is installed in a holding space within the tire skin, wherein the number of elastomers depending on the inner diameter of the tire skin and the inner width; while the external dimension and shape of the elastomer depends on the inner width of the tire skin and the tire width and shape of the tire skin, wherein the diameter of the elastomer shall be close to or no more than the inner diameter top of the tire skin and the inner diameter bottom of rim center.