Abstract: The rmoplastic composite core has a strong axial tensile capacity, while the properties of radial shear resistance,compressive capacity are weak. In the process of manufacture, transport and stringing, fiber damage failure is easy to occur, and pose a safety hazard. At present, there is little research on the bending performance of carbon fiber reinforced thermoplastic composite core, considering the structure and properties of thermoplastic composite core and there are big gaps in thermoset composite core, it is necessary to redesign bending radius. A winding test was performed on the same diameter mandrel to obtain an effective range of the reel diameter. With ABAQUS software the bending simulation model is established. The same diameter mandrel winding inside the scroll of different diameter mandrel of the equivalent stress is obtained by numerical calculation of finite element software. The results show that the maximum equivalent stress is the most lateral concentration distribution in a composite mandrel, axial tensile stress or compressive stress decreases with the increases of the scroll radius. The research results provide a theoretical basis for winding test of carbon fiber reinforced thermoplastic composite core.