Abstract: Based on a common grid and introducing the particle systems from the field of computer graphics,the paper presents a new method for visualizing the dynamic behavior of simulated water and sediment movements in digital river basin.Some of the key techniques involved in the development of the method are discussed in detail.These techniques are the data structure design for storing particle and grid cell information,the random generation of a particle that is controlled by the computational grid,the local searching and positioning of the particle,the flow field conversion from Euler representation to Lagrange representation using the self-adaptive Runge-Kutta method,and the design of particle shapes with water and sediment information.The issue of the uneven distribution of particles during the course of flow field change has been solved.The new method is tested and applied in the flow visualization system developed for the Yangtze River reach between Three Gorges and Gezhouba.