To clarify the effects of Limnodrilus hoffmeisteri, a dominant zoobenthos of Lake Taihu, on lake eutrophication, the controlled indoor experiments of Lake Taihu L. hoffmeisteri's nutrient excretion were performed by controlling the temperature and density. The effects of temperature and density changes on the excretion rate of Ammonium nitrogen(NH₄⁺-N) and phosphate(PO₄^3--P) of L. hoffmeisteri was analyzed. Based on a correlation relationship between temperature and the excretion rate of NH₄⁺-N and PO₄^3--P of L. hoffmeisteri, and the biomass of L. hoffmeisteri during 2007-2010, the potential contributions of nitrogen and phosphorus released by L. hoffmeisteri to Lake Taihu were estimated. The results showed that with temperature increasing, the excretion rates of NH₄⁺-N and PO₄^3--P of L. hoffmeisteri gradually increased; however, changes in density did not significantly affect the excretion rate of NH₄⁺-N and PO₄^3--P of L. hoffmeisteri. The annual average amount NH₄⁺-N and PO₄^3--P excreted by L. hoffmeisteri were 1925.5 t and 210.0 t, respectively. They were less than the two main exogenous nutrient sources-indirect lakeside and water course nitrogen and phosphorus amounts, which account for approximately 19.3% and 23.3% of the annual net fluxes of NH₄⁺-N and PO₄^3--P in the entire Lake Taihu sediment-water interface. The results of this study showed that nutrient excretion by L. hoffmeisteri had a significant effect on lake biogeochemical cycles and eutrophication.