Abstract: Sediment problems in the environment,and enviro mental problems caused by sediment motion are discussed in this paper.Sediment problems in the environment are very common in nature and there exist effects of sediment motion on the environment all the time and every where.It is important and necessary to combine with sediment motion to study environmental problems and to use know ledges of environmental sciences to research on sediment motion.these can be integrated into a subject titled "Mechanics of Environmental Sediment".It studies the law,control and application of pollutant(sediment particles included)transport—transformation in environment.Combining hydrotechnics,that is,mainly hydraulics and mechanics of sediment motion,and environmental sciences,such as, environmental chemistry,environmental geochemistry and hydrochemistry to study environmental problemsr elated to sedimentmotion and to research on sediment motion is its key point.Its reseach contents and methods were discussed by the paper.Thorough research on these aspects will further advance environmental sciences definitely,and to some extent promote and enrich sediment research.