Abstract: The shored mechanically stabilized earth (SMSE) wall system is a kind of narrow MSE walls designed and constructed next to the existing stable walls/slopes. However, the views regarding the effects of different connection forms on SMSE wall system are not unified. The performance and mechanism of SMSE walls still need further researches. Accordingly, by using the centrifugal model tests on SMSE walls, the measured data including settlement, lateral displacement of the facing and earth pressure on the SMSE walls are analyzed. The special performance characteristics of the SMSE walls are compared with those of the conventional MSE walls, and the effects of mechanical connections on the SMSE wall system are discussed. The results indicate that the SMSE walls suffer larger and uneven deformation both on crest settlement and on lateral displacement than the converntional MSE walls, and the connection form behind the SMSE walls has obvious influence on their deformation. The meassured lateral pressure of narrow reinforced soil mass against the stable wall/slope is far below the theoretical active earth pressure, showing that there is only the contact pressure between the stable wall/slope and the SMSE wall. And mechanically connecting the SMSE wall to the stable wall/slope is an efficient measure to help control the deformation and improve the system stability, while the unconnected wall will suffer larger displacement and is prone to collapse.