Abstract: The tensile cable-strut structure is statically and kinematically indeterminate, which is a self-equilibrate prestressed system. The calculation of initial prestress is fundamental to the following structural analysis. In this paper, a new numerical computation procedure is developed for the initial prestress calculation of tensile cable-strut structure. The force density method is the cornerstone of the analytical formula. And with the introduction of linear adjustment theory and the use of the least square least norm solution, the form-finding analysis and the initial prestress are formulated. A program is coded with MATLAB Language according to the algorithm developed in the context, and a series of numerical analyses have been carried out and verified. Numerical results show that the method is accurate and effective.