This article presents an experimental and numerical study of short-fiber-reinforced rubber sealing composites (SFRC) at different stress amplitudes (1 MPa, 2 MPa, and 3 MPa). The curves of the maximum strain varying with the number of cycles were obtained by the fatigue test, and the damage modes of SFRC at different stress amplitudes were determined by scanning electron microscope. A finite element model (FEM) was established, where fibers distributed randomly and the stress-based fatigue damage model integrating with a bilinear traction-separation law of the cohesive zone model was embedded in the fiber/matrix interface. The effect of different stress amplitudes on the fatigue damage of SFRC was investigated by FEM where the interfacial debonding behavior was considered. The predictions at stress amplitudes of 1 MPa are generally consistent with experimental data. The predictions at high stress amplitudes (2 MPa and 3 MPa) are agreeable with experimental data at low number of cycles. POLYM. ENG. SCI., 58:920-927, 2018. (c) 2017 Society of Plastics Engineers