The superimposed shear wall is a new assembly-type RC structure, it has been found more and more applications in building construction because of its adaptation to building industrialization. There are two common forms of superimposed shear wall:the superimposed shear wall with prefabricated boundary element and with cast-in-situ boundary element. The superimposed shear wall with prefabricated boundary element is more convenient to the construction than superimposed shear wall with cast-in-situ boundary element. The superimposed shear wall with prefabricated boundary element is of much more practical value in actual production. The structural improvement of superimposed shear wall is proposed. A simulation with OPENSEES finite element software was given to analyze the behavior of improved superimposed shear wall. The analysis shows that the improved superimposed shear wall not only has higher ultimate bearing capacity than unimproved superimposed shear wall, but also increases shear capacity of the interface of new-to-old concrete.