The SPMT transferring FPSO topside module vibrates when passing over deceleration belts. The SPMT vibration model is established by referring to the 1/4 vehicle model, and the dynamic equation is established by Simulink according to the model. The vertical accelerations of the suspension hydraulic system under road excitation is transformed into the spectral acceleration, and the comparison with the maximum spectral acceleration verifies the correctness of the model.Through simulation analysis, the acceleration of the module and tire when SPMT passes through the deceleration belts under different suspension damping，driving speed and deceleration belt width is obtained, and the influence of different parameters on the acceleration during transportation is analyzed.