Composite geomembranes are widely used in channel impermeability projects. The large number of applications of geosynthetic materials in civil engineering, especially in flood prevention and rescue projects, and their effectiveness have attracted the high attention of the majority of engineers and technicians. For the application technology of geosynthetic materials, the country has put forward the standardized technical requirements in terms of seepage control, back filtration, drainage, reinforcement and protection, which has greatly accelerated the pace of promotion and application of new materials. The material is widely used in the irrigation channel impermeability project, combined with construction practice, shallow talk about the application technology of composite geomembrane.