Abstract: For the design of diaphragm wall of Changzhou metro line No. 1 of foundation pit project at Huaide Station, the horizontal displacement response to different mechanical joint modes and the influences of the joint types on the stress of diaphragm wall and support system are studied through ABAQUS simulation. The results show that the maximum horizontal displacement of the joint is most likely to happen at the upper part of excavation surface of foundation pit, leading to a better guidance to prevent the joints from over-large deformation and large-area seepage. Compared with the relative flexible joint, the rigid joint is more compatible with diaphragm wall, and it can increase resistance of retaining structures to resist deformation and to reduce stress of the support system and increase stability of retaining structures. The results can be as reference for choosing the right joint mode for foundation pit project of subway station in Changzhou.