The patch material and dimension are two important factors which might affect the surgical outcomes after the aortic arch coarctation repair surgery. To quantity their acute impacts on the biomechanical environment of the repaired aortic arch, an aortic arch model was constructed and the fluid-structure interaction (FSI) technique was utilized to characterize its hemodynamics and wall mechanics. Three different patch materials were considered including pulmonary artery, ECM CorMatrix and Polytetrafluoroethylene (PTFE). The induced wall shear stress, distribution of flow patterns, and von-Mises stress on arterial wall were compared. Results showed that ECM CorMatrix patch had better performance Two different patch dimension (large v.s small) using CorMatrix patch were compared and the relatively smaller patch demonstrated a better hemodynamics than the larger one. No significant difference in terms of wall stress was observed between the different patch sizes.