Abstract: In order to solve the problems of large tensile deformation, easy notochord relaxation and, low stiffness of the traditional cable dome, proposed is a new full-assembly structure with "rigid and flexible" members, prefabricated large-span ridge tube cable dome with annular struts. The structural composition and joint construction were developed, and a structural equivalent truss model for the prestress distribution calculation was presented. The numerical model for the new structure was established by ANSYS finite element software. The structural response under the uniform load of full span and half span, and the influence of various parameters on the mechanical properties are analyzed. The results show that the new structure has higher bearing capacity and anti-deformation, which can achieve the large-span development of prefabricated spatial structures. The changes of strut height, initial prestress, structural span and, rise-span ratio have significant effects on the mechanical properties of the new structure, the influence of joint stiffness and prestressed ridge cross-sectional area on structural mechanical properties can be ignored, and the prestress distribution can be accurately calculated by using the joint balance method through an equivalent truss model.