Abstract: In order to meet the integrated design requirements of planetary gear and rolling bearing,a dynamic modeling method of planetary gear-rolling bearing coupling system based on multi-body dynamics theory and elastic contact theory is proposed. The model not only considers the dynamic interaction between planetary gear and rolling bearing,but also calculates the contact loads of each rolling body. Taking the planetary gear-rolling bearing system of wind turbine as the research object,the dynamic model of its coupling system is constructed and the coupling mechanism between planetary gear and rolling bearing is studied. The results show that the planetary gear has a significant influence on the dynamic response of rolling bearings. Affected by gear meshing force,the rolling element contact load and the bearing eccentric trajectory show the high-frequency fluctuation characteristics. The influence of planetary gears on the dynamic response of rolling bearings should be fully evaluated in the design.