During construction of the underground diaphragm wall for a pipe gallery in Chaoyang District, Beijing, the antiseepage treatment measures with sleeve valve pipe grouting were adopted to save the cost and reduce the influence of water seepage at the joint on waterproof construction for the subsequent structure due to limitations of the geoengineering and hydrogeological conditions, construction site, and other factors. This paper introduces the construction method with the sleeve valve pipe grouting process, and has verified that the antiseepage measures with the process in dealing with the flexible joint of the diaphragm wall are completely feasible.