Abstract: To meet the requirements of the low temperature performance test for the GA (General Atomics) company CSM (central solenoid module), based on the design of ITER feeder system and considering the improper of the original design, the coil terminal box shell was modified. The vertical cylinder structure was adopted to replace the lying cube structure, so the installation processes of the shell and the space utilization were optimized. On this basis, the other internal components designs of the coil terminal box was correspondingly changed, then finally the function of the coil terminal box was realized. With the large scale finite element analysis software ANSYS, elastic stress analysis, buckling analysis and seismic analysis were applied to the coil terminal box shell. The buckling analysis result was also compared with the theoretical calculation result. The calculation and analysis results show that the vertical cylinder structure of the coil terminal box is reasonable and reliable.