By combining FAS (Full Approximate Scheme) for nonlinear equations of multigrid method with Finite Volume Method, a plane two-dimensional mathematical model of sediment-transport is presented in this paper The analysis on the efficiency of this model shows that it can reduce the amount of computation greatly. Numerical simulation results of the Yellow River Langdian Water Source Project agree well with the test results of the physical model. By combining FAS (Full Approximate Scheme) for nonlinear equations of multigrid method with Finite Volume Method, a plane two-dimensional mathematical model of sediment-transport is presented in this paper The analysis on the efficiency of this model shows that it can reduce the amount of computation greatly. Numerical simulation results of the Yellow River Langdian Water Source Project agree well with the test results of the physical model.