Abstract: Vertical joints exist in a prefabricated shear wall structure, and using dry connections in prefabrication shear wall structures is appealing because it can avoid pouring concrete on site and increase the prefabrication ratio. In general, the joint width between the adjacent shear walls is small, and the deformation between the adjacent shear walls is relatively large if dry connections are adopted. On the other hand, the floor slabs are continuous at the joints. In this case, the slabs across the joint are easy to be damaged. Thusly, a construction detailing to strengthen the slab is proposed. Physical tests were carried out to investigate the damage characteristics and mechanism of the slab. The effects of the dry connection on the performance of the slab were also studied. The test results show that obvious shear failure occurs in the slab. It can be concluded from the tests that the damage in the slab of the slotted shear wall is severe and it is hard to be repaired. However, when the shear walls are connected by a dry connection, both strength and ductility can be improved. Moreover, the damage in the slab is less because the dry connections can decrease the relative deformation between adjacent shear walls. Then the slab can be repaired more easily after strong earthquakes.