Thermoplastic polyester elastomer (TPEE) has the properties of both rubber and engineering plastic. The most important characteristics of this material are its high elasticity and rigidity. So, those properties are enable to high durability against fatigue and large deformation cycles.In this study, the rebound bumper of suspension system in vehicle, using thermoplastic polyester elastomer was conducted. The plastic elastomer rebound bumper allows cost reduction and light weight on by integrating several components, such as coil spring, spring guides, blocker, stop rubber etc. In order to satisfy several component requirements such as specific compression set and Load-Displacement curve etc, we evaluated the performance change according to the design and material of the component.This study shows that how to modify the design of the rebound bumper to meet the requirments, and to choose the optimum material through the verification comparing several materials.