Abstarct: Today using fiber-reinforced polymers (FRP) is one of the most practical methods for strengthening reinforced concrete members. FRP’s easy applicability due to its low weight, high tensile strength and anti-corrosive properties has made it a suitable substitute for traditional materials and conventional methods. During recent years, retrofitting of reinforced concrete structures by bonding the FRP laminates to their soffits has grown significantly. However due to linear stress-strain behaviour of FRP and lack of yielding plateau, ductility of RC beams will be decreased. Hybrid FRP is a solution to overcome the low ductility of RC beams strengthened by FRP. In this thesis FE software, ABAQUS, is used to investigate the flexural behaviour of RC beams strengthened by hybrid FRP. Thus a model is proposed to predict the load-deflection response and failure mode of strengthened RC beams. Both of two methods show that using hybrid FRP is effective in increasing strength and ductility of RC beams.