Abstract: The three-dimensional arch structure is a new style of large-span structure, which synthesizes the advantages of the arch and dragline. As a light and highly active structure, the three-dimensional arch structure has been used widely. In order to make further research on the mechanical behavior of the structure, a 1:20 scale model test was carried. The test data show that the stress of the springing is the greatest and those of the other structure parts are less. The dragline is important to improve the bearing capacity and the ability of resisting deformation.