This paper reviews three hot topics associated with Lake Taihu environmental and ecological researches in the recent ten years, i.e. hydrodynamics and its effects on the lake environment and ecosystem, lake sediment and internal pollution loadings, lake ecological structure and functions related to algal bloom. In the aspect of hydrodynamics and its effects, a field approach to investigate the relationships between hydrodynamic parameters and environmental factors was developed. We found hydrodynamical intensity quantitatively related to sediment erosion and suspension, and further related to the transparency, internal loading and oxidation-deoxidization conditions at water-sediment interface. The internal structure of hydrodynamics in Lake Taihu has been achieved, so that the necessity of three dimensional hydrodynamic model has been built instead of two-dimensional hydrodynamic model for this large shallow lake. Relation functions of light penetration and intensity distribution as well as transparency related to seston have been established. Primary production estimate model of Lake Taihu based on the seston has been developed. In aspect of sediment and internal loading, the distributions of sediment and the pollutant in sediment have been clearly revealed. The main force which makes sediment resuspension was identified. The effects of hydrodynamics on the sediment resuspension and further on the nutrient releasing were investigated. A conceptual mode of nutrient releasing for large shallow lake was proposed and the criteria for internal loading control were put forward. In aspect of lake ecosystem and algal bloom, based the hypothesis of algal bloom formation, the understanding of algal bloom formation has been improved via the findings of nutrient thresholds and restoration ofdormancy algal spores. Investigations also revealed the phenomena that eutrophication leads to degradation of ecosystem and biota tends to small sizes. The nutrient cycling will speed up and more available nutrient will be imported which in turn enhances the eutrophicating. After investigation of periphyte effects on the submerged macrophyte, the mechanism on macrophyte disappearance was clarified. Based on these findings, new idea on eutrophic lake control and ecosystem restoration was proposed, i.e. reducing the nutrient loading firstly and restoring ecosystem secondarily. Finally, the paper made perspective for the future development of these aspects.