Abstract: Based on the characteristics of TMSR-SF1, the reactor body design and optimization method via multi-specialty coupling analysis was proposed in this paper. Referring to existing mature design codes and combining structure and function requirements of TMSR-SF1 reactor body,  the structure drawing for the reactor body was presented firstly, then shielding design analysis, heat transfer and temperature field analysis, and mechanical analysis were carried out. Finally, the reactor body design of TMSR-SF1 has been preliminarily realized by using the multi-specialty coupling repeated iteration analysis, which satisfied the function of TMSR-SF1. Furthemore, reactor structure material selection demonstration and manufacturing feasibility analysis were also performed to ensure the engineering implementability of the structure design.