Aiming at the TBM thrust mechanism of which thrust cylinder are wedgeshape arranged，a thruster mechanism multiflexible dynamics simulation model was built by using the MATLAB/SIMULINK and its physical model was established. The hydraulic cylinder was simplified to flexible model and then Kinetic equations was established by using Lagrange kinetic equation. Through applying excitation on the mechanism，the variation of transformation and driving force of the hydraulic cylinders were simulated to verify the validity of the equation. The influence of the change of the parameters of the partial structure on the deformation of mechanism was studied. The results show that the displacement amplitude of piston rods and oil cavity blocks becomes larger as the angle between the joint group on the mobile platform gets larger; within certain limits, the smaller of the mobile platform diameter and the larger of the distance between the mobile and static platform, the drive force on the mechanism gets smaller.