Abstract: After the construction of final water impoundment completes, the submerged soil in the shore area of Three Gorges Reservoir will release N andP elements into the water. Based on simulating submerging experiments with river water of origin soil sample and soil sample pretreated with nutrients, and daily water change submerging experiment of origin soil sample, it is concluded that: after the first 10～15 d of the high water level operation period of the dam,the concentration of TP and TN in the water trends to be in equilibrium, but the disturbance of the water can cause a rise of TP and TN concentration. In the simulating experiment of origin soil, the submerged soil sample had a certain ability of P absorption which declined the TP concentration by 33.4%. The results shows that the TP and TN concentration curve well conform to the first order kinetics models except the TN concentration curve of river water submerging experiment.