Abstract: Developing the space science, exploring the mysteries of the universe, are the goals of China′s aerospace technology. Radio telescope is the main detecting tool of radio astronomy. To meet the need of deep space exploration, high precision and large diameter are the inevitable direction of its development. The structural design of large diameter radio telescope plays a decisive role in the design of the whole system. This paper expounds the necessity of telescope structural design developing from rigid to flexible, introduces the principle of homology design of telescope structure and its successful application in the design of notable radio telescope worldwide. Combined with the design practice of China′s largest diameter (66 meter) antenna, the scientificalness and progressiveness of homology design are proved.