Rubber’s ability to withstand very large strains without permanent deformation or fracture makes it ideal for many applications including tires, vibration isolators, seals, hoses, belts, impact bumper, medical devices and structural bearing to name a few. These rubber components subjected to fluctuating loads often fail due to the nucleation and growth of defects or cracks. To prevent such failures, it is necessary to understand the failure mechanism for rubber materials and to evaluate the fatigue life for rubber components. Fatigue life prediction and evaluation are the key technologies to assure the safety and reliability of rubber components[1,2]. The objective of this study is to develop the failure mechanics process for vulcanized rubber components, which is applicable to predict fatigue life at initial product design step. Fatigue life prediction methodology of vulcanized natural rubber was proposed by incorporating the finite element analysis and fatigue damage parameter of maximum Green-Lagrange strains appearing at the critical location determined from fatigue test. In order to develop an appropriate fatigue damage parameter of the rubber material, a series of displacement controlled fatigue tests was conducted using three dimensional dumbbell specimens with different levels of mean displacement. It was shown that the maximum Green-Lagrange strain was a proper damage parameter, taking the mean displacement effects into account. Nonlinear finite element analyses of automotive engine mount insulator and three dimensional dumbbell specimens were performed based on a hyper-elastic material model determined from the simple tension, equi-biaxial tension test[3]. Fatigue life prediction of automotive engine mount insulator was made by incorporating the maximum Green-Lagrange strain values, which was evaluated from the finite element analysis and fatigue tests, respectively[4]. Predicted fatigue lives of the rubber component showed a fairly good agreement with the experimental fatigue lives.