Reverse circulation operation is widely used in the development of geothermal and oil-gas resources. Its operational performance is significantly affected by the temperature distribution of the wellbore and the formation. To clarify the influence mechanism of temperature distribution on resource development during reverse circulation, a numerical model was established for wellbore temperature distribution. The convective heat transfer between the working fluid and the surrounding medium was considered in the model. The influence of wellbore structure on temperature distribution was also considered. Example calculations were conducted to obtain the temperature distribution characteristics during reverse circulation operation. The temperature distribution patterns between reverse circulation and forward circulation were compared. The results show that the heat transfer efficiency between the working fluid and the formation is increased by 19% in reverse circulation compared with forward circulation. The disturbance distance in the formation is reduced by 0.3 m. The average thermal stress near the wellbore is significantly reduced. It is indicated that reverse circulation operation is of great significance for improving operational safety and enhancing the efficiency of geothermal resource development.