External fiber reinforced polymer (FRP) plates are currently accepted as one of the most effective methods of strengthening and retrofitting reinforced concrete (RC) structures. Although these plates contribute to the compression loading capacity, their application is, however, limited to situations in which tensional stresses occur. The present study was designed to investigate the application of these plates as compression reinforcement for enhanced ductility and loading capacity in concrete members. For this purpose, three specimens types were cast and strengthened with different patterns of FRP plates and subsequently tested. These specimen types included coupon samples for determination of compressive properties and strength of FRP composite plates, small scale concrete prism for feasibility study of using FRP composite plates as compressive reinforcement in concrete structures and half scale RC beam for evaluation of FRP composite plates ability to change failure mode from brittle to ductile regime. The results revealed the considerably enhanced stiffness and compression strength of FRP plates such that compressive young’s modulus and strength of FRP sheet manufactured through the wet lay-up method are 40 and 50 percent of their tensile value respectively, for pultruded FRP laminates compressive young’s modulus and strength are 90 and 80 percent of their tensile value respectively. The results of small scale concrete prism tests showed that using compressive FRP plates can increase loading capacity and ductility index of concrete members up to 10 and 50 percent respectively. The results of RC beams revealed the considerably effect of FRP plates on RC beam behavior such that using these plates leads to increasing loading capacity and ductility index up to 20 and 40 percent respectively. Results and observations during the tests showed that there is only a small possibility for the compressive plate to buckle or to debond before concrete crushing. This is because of the small size of the concrete crushing strain. In the final part numerical simulation was used to investigate using both tensile and compressive plates simultaneously for strengthening RC beams. Results show that this situation may lead to premature debonding of tensile plates. Keywords: Strengthening, FRP composites, Compressive Reinforcement, Ductility.