The effects of Limnodrilus hoffmeisteri bioturbation on nitrogen releasing from sediments of the East Lake Dongting, with the different densities and environments were studied in this paper.The results showed that bioturbation of L.hoffmeisteri had a good accelerating effect on nitrogen release from sediments, which was caused mainly by ammonium release.When the density of L.hoffmeisteri was at 1 and 2 ind./cm², the concentrations of total nitrogen in overlying water were increased by 15% and 32% respectively comparing to the control test.Appropriate increasing of temperature was helpful for vital movement of L.hoffmeisteri, which caused that total nitrogen release increment were increased by 23% and 69% respectively when temperatures were 15 ℃ and 25 ℃ compared to the cotrolling 5 ℃.Adversity stress on L.hoffmeisteri, induced by acidic and alkali environments, enhanced its bioturbation effect and also accelerated nitrogen releasing.In comparison with a condition of pH 7, total nitrogen release increment were increased by 32% and 41% when pH values were 5 and 9, respectively.Total nitrogen release increment in hypoxia was 1.52 fold compared to the aerobic environment, which indicated that L.hoffmeisteri had good adaptability and survivability to hy-poxia environment in which bioturbation was stronger than in aerobic environment.