The objective of this research is to reveal the fracture which make thermoplastic elastomers(TPEs) tougher than rubbers. Tear test was carried out at various temperatures and rates of crack propagation. Besides,a new method was developed to measure the fracture energy of TPE.It consists of a sharp razor blade applied to the crack tip of Y-shaped test specimen which is pulled apart by weights to different angles. In this case,the fracture energy is calculated from the sum of energies expended in both cutting and tearing. Comparison of the fracture energies obtained from these two methods is provided as well.