In this paper， the performance，application and composition about plastic concrete，self - congealing mortar and hardened slurry are analyzed on the basis of summarizing type，characteristic and developing course of cut - off walls material in water conservancy project. The proportions and performances of plastic concrete of some cut - off walls at home and abroad, the proportion of self - congealing slurry used in the cut － off wall of third stage cofferdam of Three Gorges Project, mechanics properties of expansive soil slurry and harden clay mortar, and proportions of hardened slurry are introduced. Through laboratory testing, the proportion of hardened slurry is obtained by optimized method, which is worthily popularized.