Overland flow produces eroding force and plays a basic rolein the study of the dynamics process of soil erosion. This paper brieflyintroduces the basic characteristics and hydraulics properties of overlandflow, and summarizes the research advances in the processes of soilinfiltration, runoff generation, the resistance of overland flow, and theprediction model of overland flow. It is shown that the motion ofoverland flow on hillslopes with complex surface conditions,and themodeling of runoff generation in the various scales will be the futuretrends of overland flow dynamics.