In order to reveal the nonlinear dynamics behavior of the three stage planetary transmission system of the shield driven cutter head,a pure torsional coupled nonlinear dynamics model is established for the number of planets,the gap between the teeth and the dynamic loads. The relative displacement between the various parts of the meshing point is derived,the system differential equation is established,the coordinate transformation of differential equations,and the non dimensional treatment is carried out. Then based on the dimensionless differential equations of four orders variable step Runge Kutta method. The transmission mechanism of the phase diagram,Poincare diagram are got,by changing the amplitude of excitation and the meshing stiffness,the influence of parameter variation on the nonlinear characteristics of the system is analyzed. The results show that with the increase of the amplitude of excitation,the system enters the two periodic state of the system by the steady state of the single cycle,and then enters the chaotic motion through the multi period motion. With the increase of the meshing stiffness,the system is in a state of multi periodic motion,and the system is stable in a single period. With increasing the meshing stiffness of ks3,reducing the excitation amplitude,the stability of the system can be improved.