Abstract: To study the shear performance of RC beams strengthened with prestressed carbon textile reinforced concrete (Prestressed Carbon Textile Reinforced Concrete, P-TRC) plates, shear tests were conducted on six test beams. The use of nail connection between the beam and P-TRC plates replaces the bonding layer and planting reinforcement anchoring, fundamentally improving the construction method. Two comparison cases and four reinforcement cases were designed by changing the reinforcement ratio of the beam and the number of carbon textile layers of the P-TRC plates. The shear failure mechanism and influencing factors of bearing capacity of P-TRC plate reinforced RC beams were explored. The results showed that none of the P-TRC plates connected by nails fell off during the shear test, verifying the feasibility of the nail connection method. The yield load of the reinforced test beam increased by 8.87%~32.54%, and the peak load increased by 9.12%~31.18%. The maximum improvement rate of the test beam with a stirrup spacing of 150 mm is 17.36%, and the maximum improvement rate of the test beam with a stirrup spacing of 200 mm is 32.54%. The reinforcement effect is more obvious under low stirrup ratio. Moreover, when the P-TRC plates is composed of two layers of carbon textile, the test beam undergoes a transition from shear failure to bending failure, resulting in improved ductility and improved mechanical performance. Finally, a formula for calculating the shear bearing capacity was proposed, and the error between the theoretical calculation value and the experimental value was within 15%, indicating a good agreement and can be used to guide engineering design.