In order to adapt to the large-scale development of dock，it is necessary to carry out innovative design research on the dock wall structure of ultra-deep dock. At present，there are few cases of using lattice diaphragm wall structure in dock wall of ultra-deep dock，and further research on its force characteristics and stability is still needed. Based on an example of an ultra-deep dock project in the Yangtze River estuary，we verify the advantages of greater rigidity and less displacement of the lattice diaphragm wall than the traditional retaining structure through the calculation of the finite element model and measured data，clarify its applicability in ultra-deep dock，and carry out the sensitivity analysis of factors such as the depth of the partition wall and the front wall in the lattice diaphragm wall. The results show that the internal force of the front wall can be reduced by appropriately reducing the depth of the partition wall. The insertion depth of the front wall is not as deep as possible，the appropriate reduction of the depth can make the structure more uniform.