Abstract: Aiming at the impact vibration of the high-speed gear transmission system in the working process,with the gear on the three high-speed shafts in a gear transmission system as the research object,this paper establishes a multi-stage parallel shaft gear transmission system model with bearings by ANSA finite element pre-processing software.The nonlinear dynamic characteristics of spiral bevel gears and involute spur gears in the complex gear train system are studied through transient dynamic simulation and modal analysis.The results show that,in the high-speed gear transmission system,elastic deformation of the shaft,bearing clearance and dynamic excitation from other gear pairs will lead to abnormal phenomena such as unbalanced load,an increase of meshing force,deterioration of meshing stability and low-frequency resonance of the gear pairs