Background: Our group have developed a new 3D printing cervical composite joint system prosthesis. The corresponding biomechanical effect should be evaluated in the treatment of cervical spondylosis. The purpose of this study was to evaluate the biomechanical properties of the prosthesis using a three-dimensional finite element model.Methods: CT data were extracted by mimics16.0 software to reconstruct the C3-C7 model of cervical spine. The model was divided into three groups: normal cervical spine group, prosthesis implantation group and ACCF group. The three groups of models in six different motion states (flexion, extension, left and right lateral bending, left and right rotation) were simulated by three-dimensional finite element simulation. The RoM of lower cervical vertebra, RoM between each vertebrae, and the stress of intervertebral disc were compared and analyzed. Results: Compared with the normal cervical spine, the RoM of C3-7 in the prosthesis implantation group showed a downward trend in six different motion states, with a decrease range of 5.27%. RoM of each segment in the prosthesis implantation group was decreased, and the decrease range was less than 7.34%. In the six motion states, the stress of each intervertebral disc in the prosthesis implantation group and ACCF group was increased. Compared with the prosthesis implantation group, the stress increased significantly at at the C3-C4 level in ACCF group. Conclusion: The novel 3D printing cervical composite joint system prosthesis can not only retain the range of motion of the cervical spine, but also decrease the stress of the upper adjacent intervertebral disc.