Abstract: There exists the mutual influence of ions and sediment in river water.And the sediment discharge and the ion chemical character are linked together.In this paper,the progress of the physical and chemical denudation in a river basin is analyzed,and the relat ionship between ions and sediment is researched according to the data obtained at the hydrological station on Jialing River and Weihe River.The result indicates that the positive relationship between the sediment discharge and ions discharge is evident,the related coefficient changes if the ions.category changes,and the relationship is different in the different river.