In order to study the flexural performance of reinforced concrete beams reinforced by TRC composite embedded prestressed CFRP bars, a four-point flexural load was carried out on 1 ordinary reinforced concrete beam and 5 TRC composite embedded prestressed CFRP bars, and the effects of slot size and diameter of CFRP bars on the flexural performance of the composite reinforced beams were analyzed. The test results show that the load increase of the composite reinforced beam is more obvious in each stage than that of the unreinforced beam. The ultimate load of the reinforced beam increases slightly with the increase of slot size and greatly with the increase of CFRP bar diameter. The flexural stiffness of the composite reinforced beam is obviously higher than that of the unreinforced beam. The increase of slot size and diameter of CFRP bars is not proportional to the increase of beam stiffness. The number of cracks in composite reinforced beams is obviously more than that of ordinary reinforced concrete beams and increases with the increase of slot size, but the diameter of CFRP bars has little effect. The ductility of the unreinforced beam is obviously higher than that of the reinforced beam. The ductility of the composite reinforced beam decreases with the increase of the diameter of the CFRP bar, and the increase of the slot size has no obvious effect on the ductility of the beam. Based on the calculation model of the cracking load of a single reinforced concrete beam proposed in the literature, a formula for calculating the cracking load of a composite reinforced concrete beam is proposed. The error between the calculated value and the test value is less than 6.5%, which indicates that the formula has good applicability.