Abstract: Cable-stayed spatial grid, which has many advantages, is a type of hybrid structure composed of tower columns, suspended cables and spatial grids. The elastic support of tower column at different construction stages and the geometric nonlinear influences of suspended cables are investigated, and the stiffness equation of spatial grid is also modified partially. At the same time, with application of certain tensile forces to the suspended cables, different economical and technological effects, including enhanced structural stiffness and decreased steel consumption can be obtained. The computational example shows that long-span roof using cable-stayed spatial grid can reduce internal forces and deflections of the members remarkably, and improve the mechanical behaviors of the whole structure.