Anchorage zone is crucial for the cable-stayed bridges and a plane frame model is presented to investigate the performance of the anchorage zone embedded with small radius U-shape pre-stress system, in pylon under different loading stages based on a summary and an analysis of the behavior of pre-stressed cable-pylons, and the expression for calculating the horizontal stress in the critic position of cable-pylon was deduced. A full-scale model test under oblique loading was conducted to analyze the mechanical behavior of pre-stressed cable-pylon according to a practical project and the stress distribution patterns of main members were obtained. The experimental results confirm the practice of the proposed method. The results show that, the pre-stress provides most vertical force to balance the cable load, and the behavior of anchorage zone has slight difference between asymmetrical and symmetrical loadings.