Abstract: The lake littoral zone, an important ecotone that is a transitional area between land and lake, is indispensable for healthy lake ecosystems. In order to make a reasonable proposal for water environment improvement and ecological restoration, it is important to study ecological structures and functions of lake littoral zones. As water environment factors change gradually, the structure of the lake littoral zone shows its distinct layers in vertical, longitudinal and axial distributions. The transverse section structure consists of zones facing land, facing water and water-level changes. The longitudinal structure consists of air, water and soil. The axial structure is the landscape change as well as the layer structures with different parts of the lake littoral zone that reflect the full view and the combination of different types of lake littoral zones. The time structure of lake litorral zones reflects the evolution rules of organisms and their habitats. Both spatial and temporal structures are significantly correlated with human activities. The factors influencing time structure include biological rhythms, climatic factors and hydrodynamic factors. Six ecological functions of littoral zones are summarized, including contaminant retention and purification, algae trapping and inhibition, lake biodiversity improvement, wildlife habitat, flood storage, deposition and erosion control.