Abstract: Single-step lock has been selected for the navigation structure of Datengxia hydroproject,and its water head and chamber dimension both rank in the top of the world’s single-step locks,which makes its hydraulic problems of the filling and emptying system quite outstanding and become the key factor of its single-step plan’s feasibility.Based on the incoming energy parameters,a comprehensive hydraulic comparison between the Datengxia single-step lock and other huge and high head locks at home and abroad is carried out in this paper.Besides,the flow conditions in the approach channels are also preliminarily analyzed.The research results indicate that the related hydraulic problems of the Datengxia lock can be solved with the state-of-the-art lock techniques,and the single-step plan for the Datengxia lock is feasible.However,detailed hydraulic studies are still needed before construction of the lock.