Abstract: This apaer is concerned with the deermination of the initial cable forces of cable stayed bridges. A forward-analysis method is introduced, in which the actural construction process is considered . The influences of geometric nonlinearity, shrinkage and creep of concrete are taken into account. It is shown that the method is more comprehensive, easier and more accurate than previous methods . With the initial cable forec determined by the present method, the final cable force and shape can be determined easily . Consequently, the workload of construction control human, material and financial resources are reduced substantially . A program based on the method is devloped The P-K cable-stayed bridge of America has been analyzed .