According to the structural and mechanical characteristics of large-scale solar-oriented devices，the optimized design is carried by optimizing the force transfer structure and making full use of the designability of fiber reinforced composite materials.In order to ensure the demands of high stiffness and lightweight and overcome the insufficient bearing capacity caused by large opening structure，the main bearing frame products with the weight-to-bearing ratio of only 5.2% are designed for large-scale solar-oriented devices. It has both the function of the spacecraft module section and the function of the mechanism shell. The finite element analysis model is developed by using two strength failure criteria，i.e.，Tsai-Wu and maximum strain.Static tests are performed，and the information such as strain is collected. The obtained data are compared with the finite element analysis results. The results show that the overall trend is consistent，which verifies the feasibility of the present design.