Through small scale model test of DX piles in lab, the test results can provide necessary basis for computing formula of settlement. A series of tests about DX piles with 22 mm diameter in sand are carried out in a small test chamber with the loading frame;the Q-s curves are derived, and then the bearing capacities are determined and compared with the straight piles in the same condition. At the meantime, miniature earth pressure cells are installed to test the stress in the surrounding soil of DX piles, so that the load transfer law in the soil can be researched. The test results show that the capacity and settlement characteristics of DX pile are much superior to the straight pile with the same parameters. For the single-bell DX pile, the location of the bell has barely effect on the capacity. However, when the bell locates on the lower part of pile shaft, the stress of soil around the pile tip increases a lot. For two-bell DX pile, the stresses around the two bells are similar, and the range of soil stress induced by bells in vertical is around two times of bell diameter. For the DX pile with three bells, the soil stress around the bells spread increasingly, while the amplitude is small.