Abstract: An analysis of the heat generation in a high speed ball bearing system of anaeroengine is considered in detail on the basis of dynamical analysis. First, the heat generation rate is calculated according to the elastohydrodynamic lubrication theory. Then, considering complex relationship of heat transfer, the temperature contribution in the ball bearing system is calculated by using the combination of the finite element method, finite difference method, system heat equilibrium method and empirical formulas. Contribution of inner heat sources and treatment of boundary conditions in the calculation are analyzed thoroughly. Finally, thermal analysis of the ball bearing for a specified Aeroengine is made. Calculation results are shown in a good agreement with the experimental data offered by Shenyang Aeroengine Research Institute.