Abstract: As the only fresh water lake of Shanghai, Dianshan Lake lies on the border of Jiangsu Province and Metropolitan Shanghai and covers an area of 62 square kilometers. The dominant factors to the formation of Dianshan Lake Wetland such as geological factor, geomorphologic factor, climate factor, hydrological factor and human activity factor etc and their interactions are briefly introduced in the paper. The productional function and the environmental and ecological functions of the Wetland are discussed. The Approaches for protection and proper utilization of the Wetland are also proposed.