Abstract: Proposed is a method for retrofitting RC beams prestressed by carbon textile reinforced concrete (Prestressed Carbon Textile Reinforced Concrete,P-TRC) plates. The plates and beams are connected by nails to improve the construction efficiency and to reduce the wet work. Three comparison applications and six reinforcement applications were designed to conduct experimental tests. Analyzed were the effects of fabric layers of P-TRC plates, the reinforcement ratio of the beam, and the strength level of concrete on the bending behavior of the beam. Compared were the failure form, crack distribution, and bearing capacity of all applications. The bearing capacity and flexural rigidity of beams were significantly improved by this method. The crack loading was increased by 28.7~55.9%. The yield loading was increased by 8.06~23.9%. The crack width was reduced by 30.2~41.1%. This method is more effective as the number of fabric layers of P-TRC plates increases. The bending resistances of the beams are increased as the reinforcement ratio increase, but the retrofitting effect of this method is diminished. Finally, the formula for calculating the flexural loading capacity of a reinforced beam is established upon the theory of bending capacity of normal section and upon the consideration of the strain hysteresis of P-TRC plates. The results obtained using this formula agreed well with the experimental ones.