The deformation behavior of prestressed CFRP reinforced concrete beams without unloading is calculated and analyzed by using ANSYS finite element analysis software. In the calculation, the method of temperature rise is used to apply the prestress, and the life and death of the unit is used to realize the reinforcement without unloading. By comparing with the experimental results, it can be seen that the numerical results agree well with the experimental analysis results. On this basis, the expanded calculation of different initial damage amounts and CFRP strengthening amounts shows that the initial damage beams have almost no effect on the bearing capacity of concrete beams, and the bearing capacity of concrete beams can be effectively improved by increasing the number of CFRP strengthening layers.