The polyester elastomer gasket is used in the steel rail or under the steel plate to play the elastic cushioning effect of rubber and plastic elastomer products. It can effectively improve the overall elastic track structure, the buffer train in by a strong vibration and impact, protect the roadbed and the sleeper, and can have the appropriate damping effect, polyester elastomer also have good insulation performance, to train operation safety and prolong the service life of rail fastener play an important protective role.