The effectiveness of strengthening reinforced concrete (RC) beams with prestressed near- surface mounted (NSM) carbon fiber reinforced polymer (CFRP) rods has been investigated. The RC beams are tested under monotonic loading. The stressing process, failure capacity, flexural capaticy, displacement ductility and deformation are systematically studied. The text results show that the new strengthening technique with prestressed NSM CFRP rods can enhance the first-crack load, steel-yielding load of beams compared to the control beam. It is worth noting that the prestress can limit the crack width all the way up to failure, reduce the midpoint deflection, and improve the service performance of the strengthened beams. The strengthening method offers an alternative way to existing strengthening method. The results provide a reference for engineering application.