In order to improve the simulation and calculation accuracy of high speed train driving gearbox temperature field and provide the support for the improving effect evaluation of lubricating oil flow channel structure,on the consideration of drive principle,structural characteristics and lubrication method of high speed train driving gearbox,the heat sources and heat dissipation route were analyzed,the accurate calculation method of convective heat transfer coefficient based on monitored data by flow field analysis was put forward,and the coefficient in the calculation formula of heating power was optimized.The influence of operating conditions such as wind speed,vehicle speed,ambient temperature and oil injection volume on the steady temperature field distribution of gear box was analyzed by orthogonal simulation method.The results show that the order of descending influence of operating condition on the steady state temperature distribution of gearbox is vehicle speed,ambient temperature, oil injection volume and wind speed.The bearing temperature is increased with the increase of vehicle speed and ambient temperature,and decreased with the increase of wind speed.With the increase of oil injection volume,the bearing temperature is decreased first and then increased.The simulation calculation error of the bearing temperature by the proposed method is less than 5%,it can meet the requirements of engineering analysis and calculation.