[Objective] The aim of the research was to reveal the influence mechanism of sediment-water exchange of nutrients in Chaohu Lake. [Method] The effects of environmental factors (overlying water, temperature, pH and dissolved oxygen concentration) on NH4+ release in sediment from Chaohu Lake were studied under controlled laboratory conditions. [Results] With the rising of temperature and the decrease of NH4+ concentration in overlying water, NH4+ released from sediment increased significantly. pH had a great effect on NH4+ release with a complicated mechanism. The largest release amount of NH4+ under anaerobic condition was about 6 times as much as that under aerobic condition. [Conclusion] This research would provide theoretical support for environmental management of Chaohu Lake in the project of leading water from the Yangtze River to Chaohu Lake.