With the rapid development of China's economy, construction industrialization has become the main development trend of China's construction industry, and the convenient, efficient, environmental protection has become the new fashion, therefore the application of prefabricated building is more and more common. Stair serves as the weak link in prefab type building, the connecting node has an important influence on its failure. In this paper, pseudo-static tests are carried out on the joints in different forms of ladder holes to study the mechanical properties of flexible hinge points filled with flexible materials, and the hysteresis curve, skeleton curve and bearing capacity of each specimen are analyzed. The test results show that the flexible hinge can give full play to its flexible characteristics to ease the stress of ladder beam, pin bolt reinforcement and ladder hole, and the bearing capacity of flexible hinge points is moderate, which can not only mitigate the inclined bracing effect under the action of small and medium earthquakes, but also ensure the stair does not fall off under the action of large earthquakes. Through the experiment comparison, the ladder hole adopts node form 2, which can give full play to the advantage of flexible material.