Based on a summary and an analysis of the configuration in composite cablepylons,the expression for calculating the horizontal force burdened by the main members of composite cablepylon was deduced according to the deformation compatibility principle;and the expression for calculating the inner force of the main members in composite cablepylon was deduced too.The full scale model tests were made to analyze the horizontal mechanical behavior of composite cablepylon according to an actual project and the stress distribution patterns of main members were obtained.Comparing to the tests results,the proposed accurate of the method was testified.