Taihu Lake is a large and shallow lake locatcd in the delta of the Changjiang River. It is an importment lake since it undertakes the drinking water supply，the transportation, sightseeing and culturing. In the last decade, this lake is suffering from the eutrophication caused by industrialization around the lake area. This paper attempts to summarize the research activities and conclusions in Taihu Lake in the past several decades. According to the current urgent requirements of the countermeasures to harness deterioration of lake environment suggested by the government, some key problems that should be addressed in the Ninth 5-ycar Plan are put forward，i.e. the lake management model which will be based on the hydrodynamic processes coupled with the diffusion and migration processes of nitrient and algae，the mcchanism of the occurrence of Cyanobacteria bloom, the release of nutrients from sediments. By the survey of literature in the international journals, a prospect about the relevant topics have been reviewed and the wantings have been revealed. Finally, the primary conclusions of the ongoing research projects have been summarized.