Abstract: Space-borne antenna distributor is the distribution and control unit of satellite on the bus bar loads.Its on-off and discharging control works importantly in ensuring that radar system equipment have the good function. In order to realize the miniaturization design of distributor, it is necessary to reduce internal wiring and optimize the layout of structure and circuit. This paper presents the new design scheme of multilayer stacking dcording to the character of the design, which is based on the characteristics of circuit design and use in antenna distributor. Compared with conventional design concept, this scheme reduces the volume size by 21%, solving the problem of internal wire-traveling, Moreover, it is convenient for the assembly, debugging and maintenance of the antenna distributor, which realizes interchangeability of the spare parts and improves reliability of product. The new structure design scheme is optimized by the mechanical and thermal simulation analysis using ANSYS software and the results meet the environmental requirements of space-borne products.Finally, it is confirmed by vibration test and temperature cycle test.