Abstract Objective To study the influence of different number of plate fixation on the stability of cervical spine after open-door cervical laminoplasty with finite element analysis. Methods The male patient with cervical spondylotic myelopathy treated by open door cervical laminoplasty was sacned by CT, and in Mimics and Geomaeic studio ,the images were processed, and to establish 3D model of cervical spine. In Creo 4.0 , the plate model was established. After assembly in HyperMesh, the finite element model of open-door cervical laminoplasty fixed with plates was constructed. The mechanical parameters, boundary conditions and loads were set in abaaus 6.1 to simulate the response of cervical spine under flexion and extension. Results ① the three-dimensional finite element model of cervical spondylotic myelopathy established in this study, including c2-t1 and intervertebral disc, has 118547 nodes and 569332 units, which is highly similar to the normal human body.②In the flexion and extension load, the activity of each segment of the continuous fixation model and the normal model was significantly lower than that of the intermittent fixation model (P < 0.01).③ In the flexion load, C3, C5 and C7 of the fixed lamina in the intermittent fixation model were significantly higher than those in the normal model and the continuous fixation model, while C4 and C6 of the non fixed lamina were significantly lower than those in the normal model and the continuous fixation model (P < 0.01). There was no significant difference in Mises stress of each segment under extension load (P > 0.05).④ The Mises stress of C3, C5 and C7 plates in the intermittent fixation model was significantly higher than that in the continuous fixation model under flexion load (P < 0.01). The Mises stress of C3, C5 and C7 plates in the continuous fixation model was lower than that in the intermittent fixation model under extension load (P < 0.01). Conclusion Through the three-dimensional finite element analysis of different numbers of plates after open-door cervical laminoplasty, we believe that although the continuous fixation model increases the economic burden of patients, but its stability for cervical spine and lamina is better than the intermittent fixation model.