Abstract:Spindle system is an important part of grinding machine, which dynamic characteristics have a great impact on the grinding precision and production efficiency of gear. To make the grinding machine spindle system as the research object, a finite element model (FEM) was established on SolidWorks, and through the finite element software Workbench to do modal analysis, and then the natural frequency of the spindle system and maximum polarization were obtained. The impact on the dynamic characteristics of the spindle was analyzed when it was under the condition of different span, different elastic modulus of spindle material and so on. The results show that the largest deformation of carbon steel plate of 1023# is relatively small, which can be used as spindle materials; Modal frequencies increase with the increasing of bearing spacing. The maximum deformation of spindle system decreases with the increasing of bearing spacing and the best supporting spacing is 240 mm.