The main bridge of Lhasa Najin Bridge is a three-tower low tower cable-stayed bridge with a span of (70+117+117+70)m. In order to study the performance of the bridge tower segment with a small radius (the radius of the splitter tube is 2.5m) and a large cable force (the maximum radial uniform load of the cable in the saddle segment is 2372kN/m), the finite element model of the 1/4 tower segment is established by ANSYS for stress analysis, and the full scale model of the bridge tower is made for test, so as to test the structural stress, the relationship between the cable and the cable The friction resistance between the cable saddles, the gripping force of the epoxy mortar in the anchoring device on the cable. The results show that it is safe and reliable to use small radius pipe for the bridge tower, and the friction resistance and anti-sliding force of the cable saddle meet the application requirements. Based on the finite element analysis and test, some suggestions are put forward, such as strictly controlling the processing and positioning accuracy of the steering saddle, ensuring the compactness of concrete pouring, and ensuring the simultaneous construction of both sides of the main beam.