Abstract: A method based on the reentry trajectory is proposed for analysis the region for ground-based Telemetry, Tracking and Command（TT&C）station, aiming at the problem of multi-day trajectory TT&C station layout optimization and resource allocation in emergency TT&C in the process of the TT&C general analysis and design in reentry. Firstly, the model between the position of the station, the reentry module and the elevation angle of the station is propagated, the detail method of the calculation of the station distribution area, in where reentry module is visible, is put forward, and finally the results of the visible region of the ground station are calculated according to the theoretical reentry trajectory. The method proposed in this paper can quickly obtain the station area visible to the reentry module, which is of great significance for the overall design and of emergency control in reentry.