In this paper, sediment samples of fine partiles were olleted from three rivers, the Nanjing reah of the Yangtze River, the Bengbu reah of the Huai River and the Yong River Estuary. Isothermal equilibrium adsorption experiments were arried out to study the variation of Zeta potential of sediment after phosphorus adsorption. It an be onluded that the absolute value of Zeta potential inreases with the inreasing equilibrium phosphorus adsorption amount per unit mass of sediment, resulting in an enhaning stability that restrains floulation. Zeta potential variation is proportional to the equilibrium phosphorus adsorption amount, but the ratio is different for sediments with different origins. This ratio ranks from high to low respetively for sediments from the Yong River, the Huai River and the Yangtze River. Moreover, the relative variation of Zeta potential is proportional to the relative adsorption amount of phosphorus, and the ratio is the largest for sediment from the Yong River Estuary, followed by that from the Yangtze River and the Huai River, whih have similar values.