Abstract: The nonlinear finite element model for the flexural reinforced concrete beams strengthened with epoxy bonded steel plates is presented. The model includes a special interface element, which is used to simulate the thin epoxy adhesive layer of the plate-bonded beam and which allows for the peel failure at the plate cut-off zone and or in the vicinity of flexure and shear cracks. This particular failure depends on two factors such as the distance of plate end from the support and plate thickness. Since the conventional beam theory can not predict the failure of such beams, this finite element model capable of predicting the overall behavior of strengthened beams including different failure modes accurately is developed. The numerical results show close agreement with experimental data available for a reinforced concrete beam strengthened by plates of variant thickness.