Objective: To analyze the different internal fixation methods of thoracolumbar fractures after spinal surgery by finite element analysis. The results of data analysis were obtained, and the validity of the clinical treatment plan was verified, which was highly realistic and reproducible. Methods: The data obtained by CT scan of thoracolumbar spine in healthy volunteers were reconstructed by MINICS software in the computer. The thoracolumbar vertebral fracture model and the reduction model were obtained by geometric pruning method. The posterior pedicle screw system was assembled according to the posterior orthopedic reduction and internal fixation program. Respectively, the different state of motion was biomechanically analysed, optimized the best option. Results: The stress and displacement maps of the pedicle screw system were analyzed in three different internal fixations. The posterior fixation of the pedicle screw fixation of the pedicle screw had obvious advantages (P<0.05). Conclusion: Finite element analysis of the optimal operation of spinal surgery has become the development of the current direction of digital medicine for clinical diagnosis and treatment to provide sufficient data to support the design of individual and surgical program development provides ample evidence.