Abstract: The cellular diaphragm wall is a novel structure, which can be used as the horizontal retaining structure and the vertical bearing structure for deep excavations simultaneously. Rather conservative attitude is often adopted in the design of the cellular diaphragm wall as vertical bearing structure due to the lack of theoretical and experimental researches on the vertical bearing behaviors of cellular diaphragm walls. Based on both the in-situ test evidences and three-dimensional analyses, vertical bearing mechanism of the cellular diaphragm walls is studied. It is found that the vertical bearing mechanism of the cellular diaphragm walls is different from that of the bored piles. By performing parametric studies, the influences of the soil properties and the structural geometrical parameters on the vertical bearing behaviors of the cellular diaphragm walls are investigated. On this basis, a general formula for the calculation of the vertical bearing capacity of the cellular diaphragm walls is proposed.