Effects of environmental factors on the release of phosphorus were studied at laboratory simulated test. The relationship between the different forms of phosphorus in sediments and the quantity of releasing phosphorus was studied at the same time. Results showed that the rates of phosphorus release from the sediment increased with rising the temperature of disturbing the overlying water. The content of phosphorus release from the sediment reached the lowest level when pH value was 7.4, high pH or low pH increased the rates of phosphorus release from the sediment. In anaerobic, the release rates of phosphorus was 30 times as much as in aerobic. Research also showed that different chemical forms of phosphorus in sediments were related to the quantity of phosphorus released from the sediments in varying degrees. The dissolved phosphorus and Fe binding phosphorus in sediments played the most important roles (r > 0.90, P < 0.01).