Overland flow is one of the main factors in slope soil erosion process,and to reveal its hydrodynamic characteristics is of great importance for better understanding soil erosion mechanism.Therefore,a series of simulated runoff scouring experiments under different slope gradients (5 °、 10 °、 15 °、 20 °) and vegetation coverage (0%、 15%、 30%) and the same water release (15 L/min) were conducted to investigate the hydrodynamic characteristics (e.g.,the flow shear stress T,stream power ω,and unit flow energy E J) of overland flow on the riparian slope of the lower reaches of the Yellow River.