Using two or more different fiber mixed form high-powered composite reinforcement, through the control of the amount of fiber bundles, to "hybrid excellent", can not only ensure the tensile strength, and can effectively improve the toughness of the FRP bar . The paper based on the theory of the composite material hybrid effect of carbon fiber and glass fiber hybrid form the CGFRP bar hybrid mode, mixed ratio, hybrid effect analysis and research, this paper expounds the influence of the main factors CGFRP bar ductility, puts forward the CGFRP bar effect positive hybrid fiber critical size, stress-strain curve, tensile strength and elastic modulus calculation method, ensure the use of performance under the premise, and put forward the CGFRP bar design idea of reinforced concrete structure FRP ductility design, improve the safety of the structure provides an effective way.