Abstract: The eutrophication of lowland rivers received great attention. When the input of outer nutrients was under control, study on the release of internal loading would be a major tool to prevent, rehabilitate, and manage river systems. The environmental impact factors that might influence the release of internal phosphorus were summarized. They were pH, temperature, DO, activities of microorganism, oxidation-reduction potential, recurrent submergence, aquatic vegetations, nitrate, and river hydrodynamics. The shortage of current studies was pointed out, and the means of settlement were suggested. There were always subtnerged plants in the riparian. It was important to know how the submerged plants influenced the fluid and how the river hydrodynamics affected the adsorption of phosphorus.