Abstract: The integrated overall thermal mathematical model (IOTMM) of a space station is built to analyze its overall thermal performance. The physical model, operation modes, mathematical description of the thermal node network and the fluid loop network are discussed, together with the composition of IOTMM for this space station, especially, the fluid loop models including the ammonia outer loop, the low temperature water loop, the moderate temperature water loop, the intra-module ventilation loop and the inter-module ventilation loop. The varying temperatures in several equipment of this space station in the manned mode are analyzed using this IOTMM.